I actually started out trying to write song lyrics, which is quite different from what I'd call "serious" poetry. Lyrics have their own thing to them in that they have to fit whatever music they're attached to. You can't fall too in love with what you do because it's bound to change somehow. I have yet to put any of my words to music, but I'm looking forward to it.
I made my first attempt at "real" poetry, when I was going through some emotional drama-trauma about a year or so ago. One day I just started writing. I have to say the stuff was pretty dark, and not all that great, but it helped exorcise some pretty nasty feelings I had at the time. It was a start. Since then, I've continued to dabble from time to time. The problem, like I said before, is that I didn't really know "how" to write. Enter The Poet's Companion.
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From what I've read so far, I'd recommend it highly.