Like most things, it's not too hard to get acceptable results, but very hard to get great results. Our beers are, at best, almost as good as good microbrews, and, at worst, not so good but still drinkable.
Stick to ales and don't even try lagering (except in the winter, if you have a cold attic or basement). Stick to mini-mash for a while.
It is a fun activity to do with friends, but I don't enjoy it enough to do it on my own.