WinMo has free apps that are ad supported too. For example, go to the Windows Marketplace and install Mo Tweets. There is a paid version and an ad supported free version.
By the way, AdBlock says "AdBlock blocks HTTP requests. It may be used for blocking unwanted ads on webpages.
It will NOT block ads in apps."
So I don't think it will stop the ads in apps...
http://www.appbrain.com/app/de.ub0r.android.adBlock