keys

my teacher gave me the c and g keys, could som 1 give me the rest of the keys? or maybe there could be a section of this site dedicated to the key a song it in. by key i mean like the chords making it up, like simple man, idk wut key its in, but the chords are mainly c, g, am what key would tht be in. also is the scale tht they use in the song always the key for the song, does the key ever change? btw i cant read music, tnx

this will give you the chords in each key.

http://www.all-guitar-chords.com/lesson.php?id=3

also check out this one

http://www.all-guitar-chords.com/chords-to-scale.php

tnx guys