Do you mean cabinets? Not sure..
Butterflywings site was pretty cool though. It covers longarms, but still alot of info.
You may be able to go to different manufacturers websites to get ideas for used machines.
But one problem, they (the manufacturers)are going to inflate their prices even for used and the abilities of their machines as well.
I agree that a "Blue Book" would come in handy.
Have you tried consumer reports? They are unbiased.