In my personal opinion, Chet did his best work in the early to mid-1950's (his LP's on Pacific Jazz were excellent, particularly the recordings with Gerry Mulligan and Art Pepper), and late in his life (the SteepleChase label). Chet, as you know, had a severe drug problem, and lost his teeth due to an infection, which made it nearly impossible for him to play his trumpet during much of the 1960's. He did a couple of recordings on the CTI label which aren't bad, if you like the Creed Taylor sound (I don't -- it's too commercial and bland for my taste). IMO, Chet was also grossly over-rated as a vocalist, unless you are looking for "music to get laid by".
One of the early Mosaic Records boxed sets reissued Chet's Pacific Jazz small group recordings. If you can find this set (now long out-of-print), it's excellent, and has a first-rate booklet about Chet's life and the recordings.
The Riverside recordings mentioned in the previous post are OK, but by the time Chet did those LP's, he was seriously strung out on heroin. If you already have many of Chet's others recordings, the Riversides are worth having, but I wouldn't start with them,
Chet wrote a short autobiography / memoir titled "Chet Baker: As Though I Had Wings - The Lost Memoir", with an intro by his wife Carol. It's an interesting read, although I wish Chet had included more details about his recordings. The book is published by Buzz Books, a division of St. Martin's Press.
