What do you mean by CodeWarrior libraries? Can you be more specific on what kind of reference are you looking for? XBee documentation, help on CodeWarrior and Digi's extension to it or the Freescale HCS08 specific reference?
Have you covered the following:
1. Product manual for XBee RF Modules which also covers partly the programmable XBee: http://ftp1.digi.com/support/documentation/90000976_V.pdf
2. The Codewarrior Help is divided into:
- XBee Firmware Library Documentation, which is divided into the Programming guide and API reference
- XBee Extensions User's Guide, which is a help on the Digi's extension to CodeWarrior
3. Personally I think the examples included with the XBee SDK are really helpful as they cover a wide variety of real life scenarios.
4. If you want a deep dive to the Freescale world the MC9S08QE32RM Reference manual is an interesting read: http://cache.freescale.com/files/microcontrollers/doc/ref_manual/HCS08RMV1.pdf
Additionally, the Freescale forums can also be helpful if your application you have in mind requires you to squeeze everything out from that tiny MCU.
My own personal gripe to Digi is not the lack of good documentation but that they have opted to embed a big part of the documentation exclusively to the CodeWarrior help - making it hard to reference online for example.
But this can be used to ease the pain: