Here are some great books for writing better Copy: ( I have read all of them). I keep them on a shelf by my computer.
The Well Fed Writer, by Peter Bowerman Effective Communication, by Ken Lawson The Golden Rules of Blogging, by Robin Houghton The Advertising Solution, by Craig Simpson The Elements of Style, by Strunk & White The Art & Science of Web Design, by Jeffrey Veen
Some Great Copywriters you can learn from: Ed Gandia, has a podcast on itunes. John Carleton, see him on Utube. The late Gary Halburt, see him on Utube too. Craig Simpson, has a podcast. Sonia Simone, and Brain Clark @ Copyblogger.com (These two are among the best out there).
Have you read my blog posts yet?
I have two Blogs, Health and Wellness, and The Copywriter's Diary