I am using a Handheld that I feel to best suit me, it's a TRGPro (trgpro.com)
it has the most internal memory you can have (8megs/2Meg Flash)
Also it's expansion slot, is CompactFlash I/II compatible, so it'll work with almost all Industry standard CF cards, and memory ( I use a 32Meg Flash card from my brother's old Mp3 player, and does a great job for backup and etc, I also use it for my digital camera without any modification to the data)
It's one of the ONLY companies on the market that has a Warrenty on the 100$ screen (funny the most expensive part, is not covered by alot of handheld companies)
It's battery life is significantly good , (they say about 8 weeks of normal usage) , but for me, its about 2 weeks of extended usage, and I use lower powered NiMH Batteries, so its not a cash drain. (unlike the Visor Prism by handspring, which has a battery life of 6 hours of continous use)
It also has that nice Indiglow backlight.
its very easy to use, also has utilities, to treat your CompactFlash card as part of the rams (being able to access it from most applications)
and currently it's only 249$ at Sam's Club.
If you want a cheap, but not beginner model, a Handspring Visor is good (149$) , but if you want like a beginner model , the Palm m100 is good (I think about 99$), but I like my TrgPro , it's best all around, uses the PalmOS.
I wouldnt go near PocketPCs, they may have all the bells and whistles, but are more expensive, and even if they have 16 meg rams, or a 200Mhtz CPU, it still tends to be less efficient, and slower than my PalmOS handheld. Karl Blessing aka kb244{fastHACK}