Email and notes tend to work. It depends on how fast an artist fills up; plenty aren't first come, first serve either.

Thank. I always hesitate to ask ppl who have full slots.

It never hurts to talk to someone about art. Almost all artists are willing to talk about how to best commission them, when they'll next be open, etc., especially if you're polite and respectful (goes without saying, but it never hurts to if anyone else reads this too). A lot of artists I've met love to share their art with everyone and give everyone a chance to get something from them.

*nod*