I used to write about music! My brother and his friend had a zine on Hardcore music: decayzine - music for freaks. It's still there if anyone wants to google. I wrote for their website, I did Interviews with bands, partly via e-mail and partly irl, I translated stuff and we wrote reviews of CDs / records and shows. It was all pretty obscure, which might have been why it was such good fun. To this day, we still get CDs sent to our house, even though we haven't updated the page in over 3 years. That was a really good time in my life. - Since it was our own webpage, we could do whatever the hell we wanted, so I have no idea about wordcounts whatsoever. I was the one who had to proof-read everything though, because everybody else was pretty crappy at spelling.
I also used to write about music for my highschool newspaper. Sadly, not many other people shared my passion for Bob Dylan etc. so I was pretty soon let go of.
Edit: I missed the advice part. I dunno, somebody said that it's hard to make a living from writing about music, which I guess is true, at least if you don't want to become a kind of whore-ish. I guess if you're into obscure music, that's good, because that way you'll get a reputation fairly soon. Yes, I have been a little semi-"famous" in the hardcore scene, it was kinda cool.