I have seen these thing and read about people using the for OBA.......Where do you find these things and what are they worth$$$$

For used york's look at volvo's, some older AMC's and Fords. For all the info you could ever want on OBA, look here (http://www.onboardair.com)
Scott

They're on AMC's, Ford's, & Volvo's, that I know of. Go look @ the wrecking yard. Should be under $25

Lots of info here:
http://www.jedi.com/obiwan/jeep/yorkair.html

brand new with the sepitine clutch for 200$ plus with a warranty....let me know i can get you a great deal on them...