I woyld not recommend Williams and Callan. They charge CPA rates ($450 to do my tax return!) and give the work to a clerk. Consequently I ended up with a letter from the IRS advising me of a late penalty and interest charge!!!
be careful with taxes. always over pay to insure you do not get auditted. I got that advice from a RETIRED IRS fellow. it was the best advice i ever got. never been audited–