I normally hate it when someone replies to a question here with nothing more than "Why don't you google it?", as it seems to be an unhelpful (and possibly flippant) response. On this occasion though I feel forced to offer that suggestion because Google seems to offer lots of possible solutions - but (because I know nothing about iPads) I'm unable to select the best one for you.
So, at the risk of annoying you (but with the genuine intention of being helpful), here goes:
http://lmgtfy.com/?q=ipad+lost+bookmarks