I think that's just how things work...using top of the line parts has always commanded a hefty price-premium, even before people were using their PC's for 3d gaming. So if by "good gaming PC" you mean a PC that integrates only the best and the latest in terms of processing, audio, and graphics capabilities, then no, there will always be a premium for having such a system.
On the other hand though, if "good gaming PC" is interpreted more loosely, you can get a NF4 board with integrated 7.1 channel audio for around $80, a decent gaming CPU for about $150, a gig of RAM for about $100, and a 6600 GT for about $175, and it will play any current game reasonably well, and completely eclipse top of the line, $1,000+ systems from a year or so ago in terms of performance...so as long as you don't always need to be right on the cutting edge, the amount of performance that you get per dollar spent on a PC actually increases dramatically over time, and this isn't about to change.