Theres tons out there.
Tougher ones:
classical gas by mason williams/eric clapton
big love by lindsay buckingham (from fleetwood mac).
Intermediate:
spanish romance by traditional(everyone knows it)
babe im gonna leave you by led zep
away from the sun by 3 doors down
needle and damage done by neil young
wonderwall by oasis
is there anybody out there by pink floyd
blackbird by beatles
beginner:
i dont know i guess the chicken song is alright the chicks dig that