Import music specialists. Not a conventional referral program; sounds like a lot of effort, but at least you don't need visitors, just time and patience -- lots of it!
Payout: $0.10 per valid track listing sent in by email (this is complicated, so read the explanation on the site carefully); this can be spent on merchandise from the store.
Help: N/A
Rating:
Return: Not strictly a referral program; $0.10 per listing you send to them
More Information:

CD Universe
Capsule Review: Referral program that shares demographic information collected from visitors with the sites that sent those visitors there.
Payout: 5% of sales to visitors who came to the site via a link.
Help: Search forms, a selection of graphics, browse menu and more. Also supplies a special front-end to the site's classical music database.
Rating:
Return:
More Information: Here

CD World
Capsule Review: Large online music store that also sells movies and video games. Real-time statistics available.
Payout: 6% of sales during any one visit by a customer entering the site via a link.
Help: A few graphics, a search engine box
Rating:
Return:
More Information: Here

CDNow
Capsule Review: One of the most established music stores online. Comprehensive referral program includes option of 468x60 banner link back to originating site. One of the most elegantly presented affiliate programs I've seen.
Payout: Sliding scale, from base of 7% up to 15% in 1% increments (top percentage for sales of $17,000 or more in a month). Payment is in Cosmic Credit (i.e. credit for purchases) or in cash if a site has earned $100 or more in any calendar quarter.
Help: Various graphics, including around 50 sets of graphics for specific bands. No search form.
Rating:
Return: to (depending on monthly sales volume)
More Information: Here

Mass Music
Capsule Review: Site selling music and videos, with somewhat unusual structure for referral program (see Payout for details)
Payout: 6% in the form of credit or 2% cash, plus $0.005 (a half-cent!) on each click-through to the site. Note: all credit built up expires after one year.
Help: Unknown
Rating:
Return/referral: (credit) or (cash)
More Information: Here

Music Boulevard
Capsule Review: Online store with huge choice of titles. Interesting referral program offers massive amounts of assistance in building your own music store.
Payout: 5% of all sales; this takes the form of credit to be spent in the store; accumulated amounts that exceed $100 can be paid in cash.
Help: Graphics, cover art, billboard and discography links, search engine, music samples and much more!
Rating:
Return/referral:
More Information: Here

SoundStone
Capsule Review: Very large music store with limited referral program. RealAudio samples are available and can be linked to.
Payout: 5% of titles linked to. No payment for other purchases, only for actual title linked to.
Help: Unknown
Rating:
Return/referral:
More Information: Here

World Party Music
Capsule Review: Online store selling discount CDs. You must place a 2"x2" or larger graphic to form the link to WPM.
Payout: 6% of all purchases made during one visit from your site. Paid quarterly if sum exceeds $25. Paid monthly if sum exceeds $100.
Help: A few rather unattractive banners.
Rating:
Return/referral:
More Information: Here