What is a "PDA browser" exactly? That's the problem. Some PDAs used slimmed-down HTML with a few hacks. Some try their best at "ordinary" HTML. Some use WAP and its associated markup language WML. So my point is you need to select a PDA and then decide how you can code for it. But even then you need to be careful. WML, for instance, is full of vendor-specific hacks and "improvements". So you really do need to test to make sure it works on whatever equipment your salesforce or whatever will be using. I don't know of any general sites as such, but Nokia have a great developers site.

Is anyone using Perl to do this? I would think they are! About CPAN modules: well, I'm pretty sure there would be some for WML. But as it's a dialect of XML anyway, XML::Writer could be useful.

Interestingly, you've hit upon a problem and an area I'm researching. What's going to happen when a new device is invented for web access? More work to make a site available through it. I'm working on a system that I'm calling a "dynamic life and information management system" to resolve these sorts of problems.

You should also consider storing your data using structural markup of some kind, and then merely altering its presentation for other devices. XML and XSLT are just one approach. A DB and some print statements are another :-)