pretty sure they don't sell the case direct.
but the way I see it you got 2 options
1) newegg's got A LOT of cases that look like they were designed by alienware's illegitimate son
2) you could buy the cheapest alienware tower they got, and strip it, and use the case
ASUS A8N SLI mobo
AMD athlon 64 x2 4200+
Corsair XMS Pro 1gb + OCZ Platinum 2gb
XFX nVidia GeForce 8600GT 256Mb
WD Caviar SE 250gb 7200rpm IDE
WinXP pro + Vista Pro + Ubuntu 7.10
+
Macbook
2.0 Ghz core 2 duo
2 gigs ram
120gb hdd