HowardForums: Your Mobile Phone Community & Resource - Cingular Phones. As I said, Howard has the best phone data, but they are amazingly good for Cingular which is where they started.
Their current recommendation is to get an unlocked Motorola V3i on eBay since that costs $300 as "mpire":http://researcher.mpire.com/research/progress.page?action=call&formName=search&searchType=form&query=v3i+&search=Search&excludeWords=slvr+pebl+mpx220+l7 +z510 shows and you can get it now and it is unlocked, whereas the expected Cingular release is May and it will cost the same since the V3 is so popular they don't have to subsidize it. Hattip to "Howard":http://howardforums.com/showthread.php?t=767791&page=43&pp=15
The real story here is that Cingular has high speed UMTS, so lots of interest there. The hot phone seems to be the "LG CU320":http://www.howardforums.com/showthread.php?t=773808 and the upcoming Nokia. These are both sliders. It's $250 right now.
The upcoming Nokia 6282 is also a slider and looks nice and should be out in a few "weeks":http://www.howardforums.com/showthread.php?t=801011&page=16&pp=15 with an estimated price of $350-400.