Please Help: Air Conditioner Leaking

[justcrash]

Ok, I have a 2007 Toyota Yaris S. It has issues. Usually it manages to suck up a piece of paper into the heating system and it sounds like a playing card stuck in a bicycle tire. No idea how to avoid that or fix it.

Now (and I gotta believe this is related) every time I turn a corner I hear water slushing behind my glove box. Water comes out and onto the carpet, and my car smells like mold.

This is the second time this has happened. The last time I took it in and they told me it was clogged?!? How is that possible and how do I avoid it? More importantly, how can I fix this? I don't want to be taking this thing in and paying to have this obvious flaw fixed every 6 weeks (it's been about that long since the last time I took it in). :(