I purchased 2 packs (police and Punk) and couple more sogs for RockBand. That's about$10
http://news.yahoo.com/s/nm/20080120/wr_nm/videogames_dc
In the two months since MTV Networks and Harmonix released the music-based videogame "Rock Band," players have purchased and downloaded more than 2.5 million additional songs made available after the game's initial distribution. Activision, meanwhile, said it has sold more than 5 million new songs via download for "Guitar Hero III: Legends of Rock" since it began adding downloadable content in early November.
By comparison, it took wireless operator Sprint four months to sell 1 million songs on its over-the-air full-song download service. While new digital music services competing with iTunes and free peer-to-peer services have struggled to convince music fans to pay $1 for a single, downloadable tracks for games like "Rock Band" and "Guitar Hero" are flying off the digital shelves










