Sounds pretty sure that you have a different wheel than the original in there. Take it to a shop and ask them to re-dish it. I wouldn't advise trying to do it yourself unless you really feel inclined to so do; it's not rocket science, but it kind of takes experience in order for it not to be an exercise in frustration.
After it's re-dished, you'll probably want to have the shop check and adjust the rear derailler also. That shouldn't cost you a lot.