Welcome to APUG. You'll find a lot of fellow photographers here willing to help you out with just about any question you may have on photography. And there are a lot of threads covering just what you are asking about.
My MF choice is a couple of FUJI rangefinders (6x7 & 6x9), they suit me just fine. And the other members will have other choices for you to consider.
I would advise the used route, and KEH is a good place to start.
Good luck on your quest.