I personally like the HP range of PDA's, it is dearer due to its NEW. It will prob blow your budget but it is a higher spec machine as you can see below.
http://www.totalpda.co.uk/HP-iPAQ-2400-New.aspx
HX 2400
Intel® PXA270 Processor 520 MHz
Integrated WiFi (802.11b) 1
Integrated Bluetooth®1 wireless technology
Integrated Compact Flash type II (CF) and Secure Digital (SDIO) slots
64 MB ROM and 64 MB SDRAM, Up to 65 MB user available memory that includes 31 MB iPAQ File Store
HP ProtectTools secured by CREDANT Technologies security application2
3.5” transflective TFT QVGA with 64K color LED backlight display, landscape and portrait display modes
Microsoft® Windows Mobile™ 2003 Second Edition software for Pocket PC modes
Removable/rechargeable 1440 mAh battery
Integrated Serial IR
Protective plastic flip cover
Pocket versions of familiar applications like Microsoft® Outlook®, Word and Excel