Actually, the author of one of them:
http://www.metacraft.com/PCGScry/
released the source on the forum. The interface is perfect, the problem is it just loads from XML files generated by PCGen. That might just mean it'll be easier in the end to start from scratch and just copy the interface.
The only thing I'm dreading about making it myself is saving/loading. The way I know to do it is to open a file, and write each and every form element to it, a huge copying and pasting job looking at all the elements there will be. That and I haven't used listboxes, etc. Nor do I actually have eVB anymore :P
There's a PDF version of the character sheet (which shows some of the math operations you do that can be automated in program)
http://www.wizards.com/default.asp?x=dnd/dnd/20030718b
2nd one down, 3rd edition, not 3.5. I know almost nothing about the game, so I can't be of too much help.
holy internets batman.