Q: iBook clamshell blueberry charging problems.

It could be the DC-in board.

http://www.ifixit.com/Guide/Installing-iBook-G3-Clamshell-DC-In-Board/114/1

Or it could be the logic board.

If you don't know what a RAM disk is, you don't have one. You have to have created a RAM disk in order to have one to worry about.

If you read the page on how to reset the PMU, you should know how to do it, but here is the link:

http://support.apple.com/kb/HT1431?viewlocale=en_US

Where did you buy the battery?  I ask because the clamsheel iBook's have not been made since 2003.  If you bought a battery off eBay or somewhere, and it has been sitting in a warehouse for 7-9 years or so, you may have just bought a dud battery.  Lithium cells will last at most about 5 years on a store shelf - after that they are unlikely to ever hold any appreciable charge again.

Was this a truly "new" battery from a reputable dealer?  One who warranties the battery and offers replacement if it does not live up to "new" specs?

Sometimes re-soldering of the DC-in contacts helps -> Link (in french, but  good photos)

There is a PRAM capacitor which sometimes causes charging problems -> Link