What is the best PDA for my uses?

I'm looking for the best PDA to fit my needs. I need to view and edit Excel files, receive emails/messages, organize appointments, organize contacts in Outlook, and link them easily. Wi-fi is a minimum, 3G is ok but I'd rather not have an additional monthly bill. I have a Palm TX and it is too bersome to use with these criteria. I've considered an Ipod touch but have my reservations. Can anyone please point me in the right direction please.