For the highest quality with a SLR, you should get either a 6cmx6cm medium format, a 6cmx7cm medium format, or a 6x45 medium format. Cameras in these sizes all have available digital backs if you want to shoot digital, but those backs are expensive - and I mean expensive.
I don't like color film and would rather shoot black and white, but circumstances sometime make it necessary to use color. for 35mm, I have older Olympus cameras, and for Medium Format, I have had the 6x6, the 67, and now the 645.
You can get film Hassys, Bronicas, Pentax, and Mamiya in most major cities. Used ones can be an especially good deals because people who are techkno freaks are trading their film for digital. I bought a Mamiya the other day that costs $3000 the other day for $400, complete.