use eMbedded Visual Basic....if you know VBA, then you're all set! it's completely free on the microsoft website!!
to use it, you need the runtimes for your ppc:
click here
and the IDE/compiler for your desktop:
click here
note: the site says that these progs won't work on WM2005, but that's not true - i wrote a program and one of my beta testers said that it works fine!
there are plently of great books out there to help you out! PM me if you want some suggestions!
Have fun!!
EDIT: eMbedded Visual Tools comes with both eVB and eC++