Financing
It's my understanding that the docs themselves don't finance but have 'deals' with various finance companies to accept payment through them. I believe Cap one participates w/ some doctors. Anyway I have some financial links I've gleaned from various members over the years, that might help you to do more research.
Links for financing sites:
http://www.medicredit.com/
http://www.p-f-s.com/
http://www.cogentfinancialgroup.com/
http://www.thfusa.com/?d=041805CA
http://www.mymedicalfinancing.com
http://www.surgeryloans.com
http://www.citerrafinancial.com/
http://www.capitalonehealthcarefinance.com/
Best of luck!