I'm doing a correspondence course in copywriting called "the Accelerated Program for Six-Figure Copywriting." (http://www.awaionline.com/copywriting/)

While it's simply unrealistic to get paid six figures for copywriting, it's helped make my writing much simpler and much easier to read.

Additionally, this sounds like stupid advice, but copy (by hand) writing you like. You'll learn (both consciously and subconsciously) what the writer is doing.