So, do you buy these from Dwayne's?

Also, check out Samy's Santa Barbara:

If you are mailing your film off anyhow, why not do it for cheaper? They use the same dip-n-dunk processors that A and I in L.A. uses, and they charge only $5.25 per roll of 120, and $8.50 for 220 (color transparency pricing). If you shoot 220, you get twice as many frames processed for the same price as the Fuji mailers.