Well, I'd rather just build one through Dell.
Here is one I am thinking about...
Dell Small Business has the Dimension 9200 w/ E6300 Core 2 Duo for $529 w/ free shipping. .
Select the options:
Intel® Core 2 Duo Processor E6300 (1.86GHz, 1066 FSB) [add $50]
Video Ready w/o Monitor [subtract $200]
Intel® Core™2 Duo Processor E6300 (1.86GHz, 1066 FSB)
Genuine Windows® XP Home Edition
FREE UPGRADE! 1GB Dual Channel DDR2 SDRAM at 533MHz- 2DIMMs
256MB nVidia Geforce 7300LE TurboCache
80GB Serial ATA Hard Drive (7200RPM) w/DataBurst Cache™
FREE Upgrade! Single Drive: 48x CD-RW / DVD-ROM Combo Drive
Integrated 7.1 Channel Audio