So I won an acoustic guitar several years ago but haven't had the opportunity to learn how to play. I've settled on teaching myself using the Internet, my own intuition, and this program I bought for the computer last year but can't find. The only other instrument I've played before was the recorder in 4th grade like everyone else.

In other words, I have no musical knowledge built up, other than a vague idea of how sheet music works because of many years of chorus (from the time I learned how to talk until I was 13). But most of my musical ability is from pitch-matching, so sheet music is almost entirely foreign to me again. :/ I see strange letters, and they mean almost nothing to me. D: I don't really have an ear for it yet.
So here's my question: How do you learn to recognize what notes are what? How do you learn what strings are what? And more importantly... How the heck do you know if you're tuning the dang thing properly?? (Okay, so it turned out to be three questions.

Sue me.

)
I found a guitar tab for a song I'd like to learn, but a lot of it doesn't make sense to me. It says it's for novice-level players, but I don't know what these things mean, so I'm still pretty lost. D:
Edit: I'm starting to get a bit of a handle on things. I found a neato online tool if anyone's interested in help with tuning their guitars:
http://www.howtotuneaguitar.org/