11bay ATX case + 300W PSU = $47 shipped

[dunbar]

Star Surplus has about 75 of these cases available as of the time I post. Check the Reseller Ratings before you buy.
Specs:

** 11-Bay ATX Case w/P4-rated 300 watt Power Supply **
Available Drive Bays:
- Four (4) externally available 5.25-inch drive bays
- Two (2) externally available 3.5-inch drive bays
- Five (5) internally available 3.5-inch drive bays
Expansion Slots:
- Seven (7) punch-out expansion slots
Other Features:
ATX Motherboard Power Connector
- Includes an ATX Aux Power Connector (AKA Extended ATX),
and ATX 12V Connector
- Four (4) Large Drive Connectors, One (1) Small Drive
Connector
- Room for Four (4) 3 x 3 Inch front-mounted cooling fans
(NOT INCLUDED)
- Room for Two (2) 3 x 3 Inch rear-mounted cooling fans
(NOT INCLUDED)
- Two (2) front mounted USB ports (USB 1.1 rated only)
- Power Switch - Reset Switch - Power LED
- HDD Access LED
- Premounted PC Piezo Speaker
- Both exterior side panels removable for easy installation
Dimensions:
- Approximately 8 x 16.5 x 18.5 inches (WxHxD)
Power Supply Specifications:
- Power Supply is manually switchable between 115v/230v
- Overload protection is built in
Input:
- 115V ~ 6.0A @ 60Hz - 230V ~ 3.0A @ 50Hz
Output:
+ 5V ~ 30A Maximum + 3.3V ~ 14A Maximum
+ 12V ~ 8A Maximum - 5V ~ 0.5A Maximum
- 12V ~ 0.5A Maximum + 5Vsb ~ 2A Maximum
- 1 year warranty
...

Not exactly a drop dead deal with only a 300W PSU, but if you are starting out small, 300W is enough.