The Minolta Dual Scan II is a great cheap film scanner. It is not the top of the line, but it is definitely the best in its class. I have seen them go for as little as $300 on ubid.com, but I don't know if I would buy from them...they were refurbished anyway. You should be able to find one for around $400 though. If you really want to get the most of your film scanner, you might want to pick up Vuescan. It is a great scanning software that does a h*ll of a lot better than most of the manufacturers software.
I don't know what kind of quality you are looking for. If this is too much, there are a number of cheaper models, but not worth the money if you are doing even moderately serious digital imaging.
Steve