The Walmart.com music service, which been under test since December, is currently pricing downloads at 88 cents per song, compared with 99 cents for Apple's iTunes.
The company said the Curb Record label is making its online catalog of songs available exclusively through Walmart.com for the next two months. The label, which includes more than 3,000 digital songs, is home to major country stars such as Tim McGraw, LeAnn Rimes and Jodee Messina.
"Customer response during our test phase has been extremely positive, with strong customer demand across a variety of genres from rock, pop, and rap to R&B and country," said Kevin Swint, Walmart.com's director of entertainment categories. "The official launch of this new service is being supported in Wal-Mart stores nationwide with a comprehensive, integrated awareness program."