Wow, a bunch of great replies and so quickly, thanks!
Fotoguy20d, I hadn't thought about the infinity stops, that sounds like it might be a big help, I'll try that soon. If I can just make it focus closer then this 150mm lens might be fine for my purposes.
Thomas, that's a great portrait, and it does show that my 150mm lens should be more than adequate, any limitations in my setup are purely due to the person standing behind the camera
mopar_guy, it's a side rangefinder. I'm prepared to spend up to $1000 or so, but only if I'm going to get good value for the money. Although I think that most used LF gear is excellent value, it's great what can be had for much less than a DSLR setup!