We have an epson scanner which works quite well with prints and 35mm negs, Epson Perfection 1260 according to the label on the front of it.
It is slow, but it is also reasonable quality and was reasonably cheap! It wont do 120 negs unfortunately and most high street places can't do them either... so if they are a medium or large format then it's either pay the price for scanning at a pro shop or break out the developer ;-)
Personally I find now that I'll take lots of B&W 35mm, process the film in the sink because it's quick, easy and cheap (knew a girl like that once....sigh, lovely lass :-)) then scan the negs and only print them very occasionally.
Good luck anyway, and break out the cameras again!! B&W is the tool of an artist ;-)