If the location is pretty close to you, then send it a few days prior to the show. If it's a few states away from you, send it a week and a half in advance. Sometimes the mail is quick, and sometimes it's slow.

And if you live in a different country, you might want to make it two weeks, just to be on the safe side.

Hi, I've never sent VV before, how many days prior to the concert do you usually send out? I live in the same country as the venue.

Cheers.