Depending on your budget, one of the best medium format general use cameras of recent years was the Mamiya 6 (6x6) and 7 (6x7). They tend to be expensive though, even second hand.
Not sure where you're based but Collectable Cameras in East Yorks has a good range of Zeiss folders, Mamiya 645, Yashica Mat, older Bronica reflex, Hasselblad etc. I've dealt with this chap and he's genuine and honest. Some of his items are in excellent condition, others less so but he'll tell it to you straight. Have a look at his list here:
http://www.collectablecameras.com/list.htm
I have a Zeiss Nettar which I used to use and gave me some excellent colour transparencies, if lacking a bit of contrast. It has a quirky range of shutter speeds: 25th, 75th and 200th. Sadly, mine developed a light leak through the back so now it enjoys retirement on a shelf alongside some old Kodaks. I have seen Nettars for sale at as low as £10 -15.
Gavin