Well I wouldn't quit my job. that gives me something to look forward too in the day, a routine more or so with the occupation I'm in now. I say get something setup with some spare cash from your job and keep your job for atleast another year if you really want to quit.
If you are going to do something, do it right, 600w hps(add more when needed), space, seed/clones, ventilation, nutes, medium, etc. all that cost money, and more money to maintain. Like so many other's said before I wouldn't dive head first into something I dont know much of. You have a job and that's more than alot of America can say. The weed can just be supplemental income, that no-one has to know about.
Best of luck