Is the "Qbank" that a lot of people mention from Kaplan? (When I googled Qbank that's what I found.) Or, are there other Qbanks, and if so, which is the most commonly used Qbank?
As said above, Qbank is Kaplan and First Aid also has a new question bank. Each of the Rapid Review books comes with a CD with ?500 or so review questions. Elsevier science also has a Qbank... anyway, lots of them out there.