If you're looking to get into LF with a NEW camera, try looking at the Shen
Hao's.
If you're looking at used, definitely check the auctions on Ebay...watch a few
of them before you jump in and start bidding - you'll get a feel for what's
what and what a fair ebay price is for whichever camera you decide to go after
and can be an educated bidder.  My personal advice is to only buy from a seller
with a very high rating.  If a seller doesn't have a 98-99-100 rating, I don't
even consider it.
Good luck.

argon