I wouldn't know what they are looking for right now, but do run a search for stock in this forum. You'll find several threads which would lead you to some stock photography sites.
Also, consider getting the [ame="http://www.amazon.com/gp/product/1582973954/sr=1-1/qid=1138760857/ref=pd_bbs_1/102-9654163-2568153?redirect=true&%5Fencoding=UTF8"]2006 Photographers Market[/ame]. It has a whole section on stock photography which includes what they are looking for, the price, contact info etc.
Good luck.