Look into the French Suites for sure! Personally, I recommend the Eb major one (no. 4) or the G major one (no. 5). I think the first two, in D and C minor respectively, are probably the most popular, not like that makes much difference.
There is also a very wicked piece I have which may or may not be accepted as Bach, called "Concerto in D minor after Alessandro Marcello." It happens to be on the first volume of Gould's recording of the Bach keyboard concerti, and really is a fantastic, and amazingly obscure (as far as I can tell) piece--and, yes, it's a "concerto" but for solo keyboard, similar to the Italian Concerto.
There is also the famous e minor toccata, which is always a great one to hear.