After the initial printing or whatnot, you could try amazon.com mp3 downloads... Xerol has one set up and you probably heard about it already, but http://www.createspace.com/
I'm thinking about trying it too
https://www.createspace.com/Products/CD/ <-- make CDs too
If you make the CD at that site, they'll send you a free proof now, and you can self-order up to like 500 copies for $2.97 (PER CD)... though shorter orders like 49 copies cost more, $4.95
If you have trouble finding all the donations you need for a "serious" printing, you could maybe try something like that