Have a look at http://www.musicyo.com/product.asp?dept%5Fid=7&pf%5Fid=302recommended as a "starter" system by someone posting on the rec.music.makers.guitar.jazz newsgroup.
Electar 4 Special PA Gig Rig Compare @: $629.00 Yo Low Price: $199.99
4-channel Powered Box Mixer with Reverb 60 Watt(RMS) - 100 Watt(Peak) Output Includes Mixer, 2-Main Speakers, 2-Speaker Stands with carry bag and 2-"really nice" speaker cables