Medisoft and Lytec obviously are good but pricey. We use Medware by Sage:

http://tinyurl.com/yuboue

Very reasonable especially if you only get once license, which is all you basically need. They do have a trial.

I didn't choose it, my practice consultant and biller have used it so it came by default. But, it's very easy to learn. Anyway, hope that helps.

Bert
Pediatrics
Brewer, Maine