You need to be more specific if you want people to help you to construct a deck. We need to know not only your primary school but also where you placed points into your secondary schools, and what table size you intend to be playing mostly at (there is a huge difference between 1v1 or 2v2 tables in comparison to 3v3 and 4v4).
I suggest not relying much on traps and more upon blades, storm dispel is good, shields are good, and so is cleanse. At small tables you might want to go more with 1v1 hit cards while at larger tables more storm lords and tempests. Tempest is good in that you can use it to clear out shields before building up for your next attack even if the next attack is simply another tempest. Normally at larger tables you want to lord as soon as possible to get the stun and buy your team time to make all its attacks and to do so without the other side messing them up.
First thing, do not waste training points on feint for a storm wizard. I have a warlord grandmaster diviner, and I use absolutely no blades or traps in my arena decks. There are too many people who carry volcanic or lightning shields from the big bad treasure bolt era. You will spend most of your buffs just clearing shields off of opponents. Trust in the power of your spells to overcome this limitation. Storm's sheer power is its one real asset in the arena. Start your deck with equipment really. You want what will give you the best combination of accuracy and power pip percentage. Stormcrusher's Galvanic Shroud, Malistaire's Wrathful Wrap, and the storm boots from Yeva Spiderkeeper are the best clothes dropped in the game for diviners. These will help until you win enough tickets to buy arena commander gear. You'll also want the Gurtok ring from malistaire's dungeon and Malistaire's deathedge as your athame. All of this is level 50 gear so it's best that you just jump up the last level, probably while farming bosses for the level 50 gear :-) The best storm deck comes from Devora Shadowcrown in the labryinth. For a wand, the shockblade of the Hoarder does the most damage, but really any wand with a storm spell will do, since its main purpose will be removing the many, MANY storm shields you will encounter. The wand will be your best friend. Find one that gives you a power pip too. The last bit of equipment I would buy is a Nightshade's choker from the bazar. They are fairly cheap and give you two 30% weaknesses (very usefull especially against balance wizards who try to one hit kill with a judgement.) As for spending training points, its pretty standard for diviners to spend ice to Tower shield, life to Satyr, and infection from death. Spending balance to weakness and reshuffle is also highly recommended. Now in the deck itself, you definitely want to include: 4 Tower shields, at least 1 or 2 Satyrs, 1 or 2 Sprites, 1 or 2 Pixies, 2 to 4 infections, 3 to 4 darkwinds (the only buff I find useful), 3 to 4 tritons, 2 storm lords, and 1 or 2 stromzillas. Other cards I find very useful are disarm (to remove apponents blades), cleanse charm (specifaclly to remove weakness or infection), and a number of lightning bats. Some other people find the bats to be surprising, but they are useful to clear shields when you can't get a wand shot and with a darkwind or boosts from clothes they can usually kill most minions in the game. Volcaninc shield (from ice) is also helpful since it will protect you from fire and strom attacks, which are the two most powerful in the game. Getting into one of the most sticky debates of the game is including bolts in your deck. A lot of naive wizards will pack thier deck with them and use them almost exclusively. Don't. It's not a good strategy and you will get beat down by more expeirenced players, while being mocked as well. Two or three in a deck is sufficent. Even better is to purchase keen eyes from the library or bazar and enchant them and stash them in your sideboard. They will be out of the way unless needed and have better accuracy on them. Speaking of the sideboard, you will want to purchase some healing spells, such as pixie, sprite, or satyr treasure cards to slip in there. I find treasure card tower shields very helpful (again especially against dreaded balance judge noobs). While purchasing treasure cards I will buy a few toughs and use them to make enchanted Krakens. These are helpful to get in a first turn hit, IF you go first, AND get two power pips. A 500 damage attack is a steep hole to climb out of. A few regular krakens in your deck could be helpful too. They definitely kill minions and provide good punch for only 4 pips. Only other thing I reccomend is two reshuffles. Using them gives you an unlimited supply of cards. Discard the first one, and use the second when you get close to the end of your deck. Hopefully your matches won't go that far since you beat your opponent into dust in short order ;) But seriously don't expect a lot of quick wins from shock and awe attacks. Be patient. Choose wisely when to strike for maximum damage. Learn when to discard to get at the card(s) you need, either from your deck or sideboard. It takes a lot of experience to successfully duel with a diviner in the arena. Good luck and happy hunting.
I have life to satyr and ice to tower shield, I also have the dispel card against myth (earthquake hurts a lot so I find it very useful to rid them), a life dispel is also nice to have, storm dispels are a must, the others cost a bit much for two pips each to cast (that is four pips if they take power pips).
I don't go with traps and although feint is good I'd rather one of my team members cast it as storm pips should be used more for quick damage before shields are up again. You should have blades, if you blade up you can still do a bit of damage through their shields. Tempest is a must and in great number, I'll go tempest wild with as few pips on me as possible to rid all the shields (two storms working together where one is constantly tempesting and the other is blading up and using storm lord or a strong tempest attack is very devestating as it only takes one powered up storm to drop about everyone if they can get a non protected against attack out... myth is therefore storms favorite PvP school to play with, followed by balance for the extra blade support, and life for healing).
My side boards are full of tempests and storm lords... not much need for reshuffle as I'll never run out of cards with that side deck and if I do someone on my team will cast reshuffle on me if I openly ask. I like my side boards to have instant group attack cards, very useful when the shuffle is bad from the start.
I agree that in the arena storm's best wand to use is a storm one. It's good at dropping storm shields but the main reason you need it in the arena is to get rid of dispels upon you without wasting pips doing so. I carry three or four cleanses as well, but I tend to use them on my team members as much as I use them on myself.
As far as the necklace goes, there are many decent ways to go, my favorite isn't the one that reduces damage as I rarely actually use those cards when they are in hand (I have lots of shields and I have dispels if needed). Instead I prefer either the necklace with two plus thirty five percent trap cards (though I don't carry traps in my PvP deck, they are still useful in that they cast zero pips to cast and you can usually sneak it in for an actual hit), or the necklace with two healing charms (if I go with malistair drake ring and athame, with a satyre and one healing charm I can self heal myself for just under 1800 health points though the pip cost is a bit high at four... but if you are playing with a life player that extra 40% healing charm can really boost their healing at a cost of zero pips to yourself, which means you can go with the malistair athame that has incoming and the gurtok ring that has health and 5% more pip chance than the other grand athames).
Sea Snake makes a very good point about setting your deck up for how big the matches are you want to play in. I should have clarified that my deck sets are specifically for 1v1. I don't play many matches with groups since I'm often on at odd times (I work evenings). In 1v1 scenarios you can only rely on yourself to clear shields, so I don't want to waste a turn and give my opponent a chance to shield again while I cast a buff. In games where you have a partner(s), there is more chance for someone to get in a clear shot when a team works together. In fact I've found that many people use storm wands in multi player arena matches to help out their storm teammates :-) Diviners certainly have the best multi damage spells in tempest and storm lord. I don't like to use tempest in 1v1 since it clears out all your pips. When using storm lord in 1v1 its best to be careful how you use since it is expensive for the damage it does. Triton, Zilla, and Kraken do more damage pip for pip. Lord is best used to clear out minions and set up your opponent for a powerful shot like Triton. Very useful for a KO late in a game. Its best to make sure your opponent doesn't already have a stun shield (or four) when doing this. That is why I only carry two in my 1v1 arena decks. I find I don't use them much other than that.