Bogey, get the missing string, get someone to tune the guitar for you and get a few chords together e.g. E, F, G, A, C, D, and maybe Am and Em. These will allow you to play literally thousands of songs. There are some great internet resources for chords of well known songs. There's a search engine on www.tabrobot.com. Then you just gotta practice. Stick to the acoustic for a while because let's face it anything sounds great on an electric so your mistakes will be more obvious on an acoustic.