The best copywriting courses are:
a) study all of Michel's portfolio, plus his copyonfire.com dvd course
b) get John Carlton's course, starting with the cheap date at marketingrebel.com (as someone noted, the swipe files in the insiders' club, plus Carlton's answers to emails etc, is very valuable, I'm an insider)
c) Dan Kennedy's advanced copywriting in a box (get from 'successjunkie' licensed seller on ebay.com)
Other excellent courses include: Brian Keith Voiles' Admagic, Robson's "Make your Words Sell" ebook (nice job on that, it's what I first read about online copy), Bob Serlings' Power Copywriting for the Internet course.
The video critiques at Michel's
www.thecopydoctor.com and Brian's briankeithkillercopyclinic.com are exceptionally important to get.
other free resources, hardtofindads.com, all of Michel's articles on his site here, thegaryhalbertletter.com .. study of of Corey's ads at
www.marketingtips.com ...
I haven't tried the Masterson course, you can read feedback on it at AWAI's forum.
The best use of copy dollars is, imho, first access the video critique sites - that's immediate and useful... then get all the books (ogilvy/caples/collier/etc) and ebooks (MYWS), then get the longer courses, then when you're ready, hire Michel and Carlton for copywriting coaching support. I would do that sequence, for the same $ as attending a seminar type event.
It's been the wisest dollar use for me of any of my business expenses by a large margin. And, you have to be prepared to act, and use the valuable tips, apply them, that these gifted professionals share with you.
I always test everything out, so far it's all been on the money, and made me money, all the tips I've gotten especially from Fortin & Carlton.
Ken