Here are some useful links if you want to either know more about copywriting or maybe even become a copywriter yourself.
Wikipedia Copywriter page - There's a page about copywriting on Wikipedia!
Was Karl Marx really an advertising copywriter in disguise?
I get a lot of junior copywriters emailing me to ask if I can mentor them or give them work or tell them what direction to take. I help where I can but with five kids, a demanding wife and several businesses, time is short.
I would say to any copywriter starting out. Make sure you read these books first.