Can the email be downloaded from the PC for later browsing/answering from the device? You can get Palms with wireless email capability, but the service is pricey. If you just want to transfer to/from the PC, Palms can do that now. Everything else is within the capability of the Palm.
That's the Palm Zire 31, with a list price of $150. You can go with the Zire 21 for $100, but it's only a black and white screen, and color spoils you real fast.
Prices for other models go up from there. There are also closeouts on recently-discontinued models, like the T3.