Liv Tyler obsessives -- all three of you -- will remember this lovably sloppy teen flick as the one where she has to figure out if she wants to lose it to the shy, sweet kid, as opposed to that other movie where she has to figure out if she wants to lose it to the creepy older dude (that was Stealing Beauty). For the rest of us: from Allan Moyle, director of Pump Up the Volume, another tale of rock saving lives, this time of the kids who work in the last record store where it's about the music,…