Sweet, I started teaching myself guitar, but it hasn't gone anywhere really (because my guitar is a piece of crap!) And I learned how the play the piano from those little kiddie books. Hey they work and they teach you the best.
Teaching yourself to play an instrument is duable but make sure you know music theroy and can read notes (both of which you learn whith piano I think) but it makes you sound really stupid if you dont know any theroy. And if you want any tips for what to start on for guitar then pm me (I've been playing for 7 years)
kewl i'm teaching myself guitar. the site that helped me most was www.ultimate-guitar.com figure out how to read tabs then go there and search up any song you want you'll learn to play it in no time. I reccomend you try Brain Stew by Green Day its only about 5 notes. Repeating over and over and over and over and over... you get the idea.
if you want any tips, PM me, i've been playing piano since i was 4