Only one Palm PDA has built-in Wifi...the Tungsten C...at $399 plus tax, shipping/handling, etc. That seems a little over your cap unless you have an old Palm to trade in or can find another discount option.
Most of the other Palms can be connected to Wifi by filling the PDA's only memory card slot with a WiFi adapter. This means you won't be able to use a memory card while on the internet. In addition, these cards typically run around $100 and help delete your battery power faster. The Tungsten T5 is currently advertised with a FREE SD WiFi card, but it is also $399.
Here is a comparison chart of all current Palm PDAs.
If you are willing to go for a PocketPC, you'll have a lot more choices and at much lower prices. HP is currently the leader, but they tend to be overpriced and have short warrenties. You can view their complete line here. As you can see, their cheapest is $349, but that includes built-in WiFi.
Dell is by far the best deal, with their WiFi-enabled models starting at just $279. You can compare both lines here. I would recommend a processor no less than 400MHz and 128MB ROM as anything less is already becoming obsolete. Also important to note is Dell is ending the X30 line shortly (even though the $349 X30 High is still one of the most powerful PDAs out there), and will not support the next version of WindowsMobile (due out soon). However, the newer X50 line does not offer WiFi for less than $399. (Watch the prices though...Dell offers a 15% discount very frequently.
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Your best bet may very well be getting a Palm E2 for $249 and trying to find a cheap SD WiFi card, but I highly recommend you look into the PocketPC options, as they offer much more bang for the buck (and will last longer, too).
Hope this helps,
John
I dont know very much about PDA's but was given a $375 budget to pick whichever PDA I want as a gift, since I have alays wanted one. I definitely would like it to be WiFi capable, I prefer Palm as an OS. I will mostly use it for organization, scheduling, address book, type functions and as an MP3 player... any suggestions

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