First thing I'd like to say: good job not calling him the second you found out he was home. A lot of girlfriends would do that, and as sweet as it may seem, I know guys can get slightly annoyed by that.
Anyways, I think calling him is the best option.
You don't know why he hasn't contacted you since, right? So, if you email him he may not answer. He may be busy, or he may just be being a dick -- and if he's busy and doesn't answer soon, it would just add to your annoyance. The same goes for texting. Calling him is the best option because right as he picks up, you have a hold of him and he can't ignore you in any subtle way. (I'm not saying he's ignoring you, it's just the only word that seems to fit there.)
Even if he is busy, though, he should've had the decency to tell you he's home. It wouldn't take long. He had enough time to post on his MySpace and Twitter, yeah? He could've picked up the phone and texted you or called you to let you know, too. If it wasn't for you checking his band's MySpace and his Twitter, you wouldn't have known that he was home, and being his girlfriend and all, it's rather important for you to know these things.
I hope everything goes back to normal and he has a good reason for not contacting you.
Edit: I still think calling is a good option, but reading the comments below texting is also a pretty good idea. Either or, I guess.