It's a bad time for your accountant to not be returning your calls. The doctors I work for will be meeting with our CPA's next week to do a year-end review, which they do every year. I'd be pretty miffed if an accountant wasn't accessible for a bookkeeping milestone like year-end.
Wish I could be more help as far as tax rates, but those vary from state to state and some slide based on taxable income, plus they may differ based on type of corporation, etc.--
Well, keep bugging your accountant - or try another one.
Deb