1) How much money to spend (i.e., $1000 - $100,000)
2) What types of projects will you do (i.e., record bands, record drum tracks only)
3) What quality level do you want your studio to produce (i.e., demos, pro level)
4) Now that you have answered these questions - go back to #1. Because it will cost about $1500 - $5000 to get a decent setup to record drums or a demo for a band. That includes the cost of a computer, interface, recording software, microphones, cables, head phones, monitor speakers, etc.
Please write me if you would like to discuss this off line.
BTW, I have a studio and I have produced, engineered and played a few independent CD projects. So, I am not trying to come off as a "pro-level guy" but I have been doing this for a bunch of years and I would be happy share my experiences with you.
Earl is right. That question is a little broad. It is like saying I want to race, What car do I need? We need more spicific information. You might check with some local studios unless you want audio and video. See what I mean? Just a wee more info!