ToddBrown,
Fill in your location. There might be a board member in your area who could help you out locally. Besides it is good manners to fill out your bio anyway.
Supersports were made from 1975-1978. Some say that the 1978 is actually as fast as the original 1969 cb750. They have rear disc brakes, and a plastic tailsection behind the seat. I like them so much I own two (a 1976 and a 1978) and might be going for more this weekend. The 1977-78 f2 f3 bikes have the comstar wheels, dual disc front brakes (much better brakes), a sliglty improved rear disc brake, and a different head. Due to the larger valves in the head you typically don't get more then 30,000 miles without at least a valve adjustment, and if the bike has been beaten you may have to do the top end. There are exceptions to this but this is what I have observed.
Personally the supersports are a more refined bike than the drum brake K models. Their value hasn't held up lke the k's either and you can routinely score them for under $1000 in good shape. The two I am looking at this weekend are $800 and $300 respectivly.