A previous poster mentioned Mark C.Gridley's jazz text;it has his top jazz recordings list and is a good overview of the subject.
Here are a few to get you started:
Early jazz--Louis Armstrong, hot 5/hot 7 recordings
Swing--Ellington,Live at Newport
Bop--Charles Parker,Ornithology
Hard Bop--John Coltrane,Giant Steps
Cool--Miles Davis,Kind of Blue
Modern--Bill Evans,Sunday Live at the Villiage Vanguard