I have just finished building my office system:
Western Digital Streamer.............($100)
WD external hard drive................($135)
5" LCD TV monitor......................($50)
Zero 24/96 DAC/Amp................. ($130)
Sansui AU217 amp..................... ($21)
Wharfedale Delta 70 Speakers.......($100)
Cables, inc speaker cables............($30)
Stands......................................($35)
4 gang adaptor...........................($10)
$611 - buying used helps

- I could have shaved $255 off if I had used my spare Denon CD player ($30) as a transport instead of the media streamer etc.
If I use the PC optical out that would bring the price down as well...but my PC sound is a bit temperamental (blippy)