I'll just tell you what I got and what I'm getting and what I'm doing with it..
I just got a Palm TX and it's pretty cool. Got it from BuyDig.com
for $255 when they usually go for $299. Anyway, I'm using it for med programs. All I have for it right now is epocrates, which is free, but not really what I need, so soon I'm buying Taber's Medical Dictionary, which would be very, very helpful in class. I'm also going to buy a package called Nursing Constellation from http://www.skyscape.com
which comes with Davis's Drug Guide, RN Notes: Nurses Clinial Pocket Guide, Nurses Manual of Lab and Diagnostic Test, and a couple other extras. That whole package is going to cost me about $126 from http://www.skyscape.com
I got the Palm TX because it does everything I need it to do. It'll hold programs that I want for nursing school (such as those listed above). It takes SD memory cards so if I need extra space I can port it. It has wi-fi, so I can connect to wireless internet, which is just convienient. It has bluetooth, which is also convienient. I can use it as an organizer, leave memos for myself, ect..
If what I said above sounds like something you might want then I reccomend checking out the TX. You mentioned a pocket PC, and those are usually more geared towards media, but I suppose can do everything I listed above. I already had a laptop so I didn't need something similiar, so I got the TX. Pocket PCs like the HP you mentioned are generally more expensive and are geared towards different purposes. I also wanted something small I could fit in my pocket during clinicals, and some pocket PCs can be a little big for a pocket. The TX is 4.5'' long and 3'' accross, and a pinch over 0.5'' thick, so it's great for a pocket.
My best advice: write down what you're looking for and what you need in a device, and ask yourself what you'd do with it. Then search for the products that deliver what you want, and then pick the best deal. I know when it comes to computers people get carried away and get stuff they'll never use, which ends up costing them more. But I do reccomend paying a little extra to have something decent than be really cheap and regret it eventually. And be aware that after you buy your product that you'll have to buy software, which cost money (if you want good stuff). Like I said before, I spent $255 for the TX and now I'm spending $126 for software, so that's $381 for the total package. But I'll go ahead and reccomend the Palm TX, because for what I needed in a PDA I really couldn't find a better deal.
Hope that helps!!!