Professional tax & service tax - when is it required?

i have started a IT company in Hyderabad. I had opened my company last year but i was not fulltime into it. From this nov, I have started fulltime working on it. Right now there are 4 people working in the company.

I would like to know whether professional tax & service tax is applicable to me. If yes, what is the procedure for filling it.

thanks a lot for helping