I don't really understand how you can 'accidentally' sell something on bazaar. If your worried that it will happen again, put them in your bank chest in your house so it can't 'accidentally' get sold ever again :x
Its been a while, but I think its the sheep in the crypt area of the Ancient Burial Grounds in Mooshu.
And yes, when crafting for a quest, IMMEDIATELY do something with it - put it into the bank if need be.
And check this out - if you are crafting the Grizzleheim House (and how you could with the lack of Stone Blocks), you can keep the Ornamental Step Stones on your dorm room floor. Easy to count them too.