The Cog Is Dead [link]
Ghostfire [link]
Escape the Clouds [link]

And if you don't mind something loud, Ebon La Furies [link]

Is anyone else just imagining the groans and grunts of fat nerds masturbating to classical/orchestral music?

Abney Park: [link]
Dr. Steel: [link]
Also: [link]

The only steampunk music group I know of are "The Men That Will Not Be Blamed for Nothing." It's been a long time since I've bothered to search steampunk, but that group sounds like rock to me.
I'm not really sure what steampunk music would be, but electroswing comes to mind for some reason other than classical because most electroswing songs sound old but have contemporary beats to them.

How about Steam Powered Giraffe?

What would steampunk music even be? Classical, since we're talking victorian england?

no I only know of the steam punk con coming up in feb