The biggest problem with conversions is text placements. Whatever your layout is, you need to change it. I can't say what's wrong without looking at it(and sometimes it *looks* fine). You can make five almost identical sites in content and layout and yet one can convert much better(or worse) than the others.
It could be a lot of factors, but the best thing to do is change ad layout.
What have you lot found to be the best way to monetize your proxy site?
Adsense on the main page, adbrite/adversal on the proxied.
Testing waters with 2 other companys right now though so we will see.
I refuse to use AdSense on any of my sites.
However, I've achieved great success with AdBrite. Just got an account setup with Clicksor, so we'll see where that leads.
Many people are saying Adbrite are blocking proxy sites, is this true?
No. I'm currently using AdBrite on my proxies and have been.
My three best performing advertisements were:
1. Full Page Ads
2. 468 x 60 - I don't use 728 x 90, but that might perform better.
3. 300 x 250
If my advice is helpful, you can use my AdBrite referral link.