Hi Drummers, nice to meet you!
I'm actually a keyboardist but I saw this topic from the main forum page and thought I'd chime in.
Sidereal, you're near me, man. What kind of music do you play? Into Latin or jazz at all?
I've paid (and heard of side guys being paid) quite a range ... if you're a full-time musician and an in-demand session guy who's played with better-known artists (but you're not "famous" yourself, beyond a regional level), perhaps toured with them, etc, expect to get $100 per song minimum, closer to $150. I know one guy who charges $250 per song, but he heads his own group and is fairly well known; session work is not his preference.
You have to take into consideration how much rehearsal with a band is involved. Rehearsal can be anywhere from free to $50.
I think type of music may play into this, too. One session, for example, I played bass. I got about $125 per song, but there was quite a bit more rehearsal (with band) than I would have liked. Other sessions have been even less lucrative. But, I don't go chasing studio work, so I don't find it ... I'm usually on the paying end.
EDIT: Sidereal/Jim B.
, I think I know you, man! Connection: Digidesign. Right??? PM me.