How to become an actress?,

It's funny, I heard a professional actor once say that he ended up firing his agent, because he wasn't getting parts he wanted. This isnt to say the agent was bad at their job, but rather that agents often suggest certain people on their books for certain jobs - generally because of looks, their abilities, etc. But he found that he wasn't exploring all areas of his abilities (or testing new areas), and getting typecast a bit. So he fired his agent, and found that he had no trouble getting offers for work. In fact, he said it was the best thing he'd done for his career. This guy is fairly well known, and I was just wondering if anyone out there has had a similar experience, and if this only works for already known actors. I mean, is it always necessary to tell aspiring actors to find an agent, if there is a perfectly legitimate (and maybe more slightly difficult, but nevertheless do-able) alternative?

Just wondering... (not being an actor myself...)