Like its creator, who has recorded some of the most bilious, complex songs ever written (plus cartoon-animal love ballads), ''Songbook'' is uncategorizable. Neither live CD nor greatest hits, it combines solo piano rerecordings of '70s Newman masterpieces (''Sail Away'') with soundtrack instrumentals and a couple of his best '90s tunes. Newman doesn't top his lavish originals, but the deepened blues of his aged-whiskey croak sear the dust off classics like the all-too-timely ''Political Science.''

