I'm quite sure, that you know it, but this site helped me a lot, when I was a really beginner in PDA world. There's plenty of informations, freeware and good forum as well.
Here's another link I've stumbled across, there's a couple of nice freeware app's but the rest you've got to pay for if you really must have them. http://solsie.com/category/windows-mobile/
OK so I know that this isn't specifically relevant to PPC's but it does relate to the Freeware thread for this topic....maybe I should have started a new topic??
Anyway, here's a list of some really useful freeware apps I've come across whilst checking out my other forum sign0013: I'll try not to stray away again!)
Another really good one is PFE Program File Editor I use it at work but tracking it down is near impossible as I've had a quick scourer of the Internet and only found reference to it, no downloads as it is now obsolete.