Online auction service eBay is stepping up its experimentation in the digital music space. The company today (Sept. 23) will begin selling major-label content as downloads via an alliance with upstart

Online auction service eBay is stepping up its experimentation in the digital music space. The company today (Sept. 23) will begin selling major-label content as downloads via an alliance with upstart download service Pass Along Networks.

Franklin, Tenn.-based Pass Along -- which also makes its bow today through its own Web site, in addition to the eBay distribution -- claims a catalog of more than 200,000 tracks from all four majors. Pass Along, which offers tracks in the Windows Media format, is expected to expand its catalog to more than 500,000 tracks by the end of the month, with music from a host of independent labels.

The deal marks the first time eBay has been involved in offering full-song downloads from any major label. The company started testing digital-content transactions back in July, but the offerings so far have been limited to independent music and ringtones. eBay partners who have sold content as part of the six-month trial are Warner Bros. Records, which is auctioning ringtones, and indies Jeff O's Retro Music and iHoopla, which are both selling song downloads.

The wrinkle to the Pass Along service, which by and large functions like any download store, is that it offers free music incentives to customers who persuade others to purchase music through the store. Pass Along users can send individual song links or collections of song links to friends by e-mail or through popular instant messaging (IM) services from AOL, MSN and Yahoo! Referrals that result in a purchase earn the initial user points that are redeemable for music downloads. For every 10 songs passed and purchased, users earn a free song. Users don't need to register with the site or buy tracks to begin passing music.

Pass Along also claims to be the first download service to accept the Paypal online payment system for customer transactions. Paypal, a credit-card alternative, is a favored payment solution for eBay users.

As part of the launch, Pass Along is teaming with RCA Records to auction a pair of 15-minute phone conversations with Avril Lavigne through eBay. The winning bidders will receive a call from the artist and a download of her latest album, "Under My Skin." Proceeds from the auction, which ends Sept. 30, will go to charity.