If you are using simple email and zip submit banners, then your conversions with your type of traffic aren't going to be very high.
People see these offers almost every day, especially people on MySpace.
Even some of the nitwits on MySpace know there is no way they are going to get a "free ipod" or "gift card" just for handing over their email address. they've seen these types of offers spammed all over Myspace and many people are "immune" to them no matter what you do.
Listen to what these other guys have said, search for some other offers out there that are more targetted to your traffic.
You can join more than one affiliate network. Join a few others and see what they have to offer.
Check out what your competitors are promoting on their site, do some digging and see what network they are getting their offers from - if they have targetted offers that is. If they don't they are probably seeing conversions like yours, so too bad for them.
CPA offers can make you money, but they definitely aren't a "magic bullet" (not the blender, which is excellent BTW!). You aren't just going to post a bunch of simple email and zip submits and see cash rolling in the next day.
It's a good sign you are seeing lots of clicks on your offers because that means it isn't because they aren't being noticed.
The low convo's are because someone clicks on the link/banner and says to themself, "I've seen this before, no thanks!".
Work on finding some more targetted offers that will make your visitors say "Hey what's this?" or "This looks cool" (okay lame examples, but you know what I mean).
If you do that, you should see better convo numbers. If not, then, well.....kill yourself.