By far, best song when high is Stereo by Russ Thompson. He's a local artist where I live. My best friends heard him on the radio one night and could swear they knew every lyric of his song as he sang them. It really gets you mellow, man.
Alice in Chains rocks !! a tad depressing though nothing sad really hits me much when i'm stonish, i avoid funerals when i'm stoned after i once went after a bowl (or two )and was caught sporting an acid grin
Bad company, ready for love
audioslave, shadow on the sun
snoop dog, aint no fun
sneaker pimps, six underground
Just a couple of the tunes I like when I'm high anyway.