I posted something like this last year and got flamed and called a spammer, but fuck it.
I've had an e-music subscription for years off and on- cancelled it last fall, but I'm thinking of opening it again for Coachella. It's not as good a deal as it used to be, but you can still get 75 downloads a month for $20. They are standard mp3s.
I started searching for some Coachella artists and decided to just search for ALL of them and post who's available. A few of these might be the wrong artists...I checked on some, but this just means I got a hit on their name. It's possible that there might just be one track on a compilation available. Sometimes, you can only get older material. (For example, they have "Arular" from MIA, but not "Kala"...some early Battles EPs, but not "Mirrored") On the other hand, sometimes you can get a whole back catalog. Also, sometimes they have exclusive live stuff...quality is usually mediocre, though.
What I did last year is do the usual Myspace/youtube research, and then download stuff from e-music for the ones I really loved. It was also nice to have after Coachella...I went and got Gogol Bordello's whole catalog afterward.
It would probably be easier to list who they DON'T have, but I didn't make the list that way. I did think it was funny that Tegan & Sara, Death Cab, Rilo Kiley, and a couple other searches got me a rather snobby message that e-music "doesn't carry mainstream top-40 music"
The Raconteurs (some live tracks)
Sharon Jones & The Dap Kings
Les Savy Fav
Scroobius Pip (but not Dan Le Sac)
John Butler Trio
Architecture in Helsinki
The Bees (there are 2 listed…)
Portishead (one track)
Kraftwerk (one track)
Café Tacvba (one track, with David Byrne)
Sasha AND John Digweed (but not together)
M.I.A. (you want the one that says XL after it.)
Cold War Kids
Minus The Bear
Bonde Do Rolle
Curses (not sure if it’s the right one)
Sebastian (wrong one, I think)
Grand Ole Party
New Young Pony Club
Love & Rockets
My Morning Jacket
Simian Mobile Disco
Dimitri From Paris
Linton Kwesi Johnson
Duffy (Wrong one I think)
Shout Out Louds
Anyway, there you go, flame away. I don't work for fuckin e-music, steal if you want, buy CDs if you want, download cheap legal stuff if you want, I don't fucking care. Just putting the info there if anyone else cares.