Alienware: Currently owned by Dell but with surprising independence this far after the acquisition. They sell high end gaming systems. However, high end in 2009 (or earlier) is not the same as high end in the current era.
http://en.wikipedia.org/wiki/Alienware
The model number (not included in this ad) will tell you what the value of the system is in the current market.
Just FYI, a 20 in Dell (alienware re-branded possible)LCD plus the operating system could easily be worth the 300.00. A 20 in CRT monitor… not so much.
More info from the OP should generate those serious buyers. :)