With respect to ebook reading, here's my advice:
https://www.mobileread.com/forums/sho...80&postcount=3
When I was looking for a new device, I eventually went with a free Samsung SCH-i760 from Verizon. Nice phone, good as a PIM, but a mediocre general purpose device. If I had it to do over again, I'd spring for a bigger screen and no keyboard.
If you have a cell phone plan that has "New Every 2" or some such, you might look over their offerings. Beware of required data plans, though. I don't have to have one (corporate rates, etc.) but some people may have to sign up for those.
If I was looking a used PDA, I'd probably go for a Dell X51V. My plain X51 is still good for ebook reading. For new, either an HP 111 or 211 is about your only choice.
Regards,
Jack Tingle