Hi Richard,
What do you consider "economical"?
I know guys who do good work between $2k and $20k... obviously the more money you spend the better their conversions.
And of course, the name of a good copywriter is a big bonus when you're trying to get JVs.
I think the forum you're thinking of is "AWAI"... but between you and me, their course isn't that great, and as a result the quality of writers is pretty unpredictable.
-Dan