logitech THX are the only computer speakers i'd suggest buying.
They're really worth saving up for.
Newegg.com - Logitech Z-2300 200 watts RMS 2.1 Speaker System
Sister has these... they rock.
I had these:
Rage3D - Logitech Z-5300 Review - Introduction
Decent, but i nuked them pretty quick.
Get the Z 2300...
http://cgi.ebay.com/Logitech-Z-2300-...ht_5772wt_1391
$100 isn't bad at all...
Summary is... anything thats not logitech THX is prolly chit.
even the new logitech THX look ****ty... the Z 5500/5300/2300 series were good though.