A little update on my progress:
I have, um, somewhat "mastered"
Horse With No Name, by America. It irks me that it's the first song I will have ever learned to play all the way through, because it's kinda lame, but... I'm thrilled that I picked up on the rhythm and the chord changes almost instantly (I already knew the song by heart). I was even doing it without looking, and singing along!
Tomorrow night is my first formal lesson with some guy who's been teaching for 17 years. I hope he has a sense of humour, because he's sure going to need one...
Cheers (and rock on, dudes).