Gotta agree with the earlier poster -- depends on lots of factors. Where you're at right now, genetics, what your idea of "progress" is, etc., etc. Just understand that if you start now, and STICK WITH IT, you *will* make great gains. It may take a couple months, it may be a year or two before you feel totally transformed. As with most things in life, the iron game is about PERSISTENCE more than anything else.
Oh yeah, be prepared to hear a lot of conflicting advice. There's a lot of juvenile "my workout can beat up your workout," especially on this site. Still, read, watch and consider all of it; you will figure out soon enough how to pick and choose the things that work best for you.
Now go get lifting, Young Grasshopper!