I think I have the right place... I wanted to help contribute a bit.
I've been using the TRENDnet TEW-441PC and it works perfectly well for monitoring and packet injecting goodness. I'm pretty sure it uses the madwifi drivers, but I don't know for sure.
When you first put the card in, it creates a VAP that's in managed mode. I use airmon-ng stop ath0 to destroy it. Then airmon-ng start wifi0 to re-create the VAP, this time in monitor mode. After that, everything works great.
I hope that helps....
A little nonsense now and then is relished by the wisest men.