I don´t have that much of an idea as to the price range right now... But I know that this config will get considerably cheaper and might be one hell of a good deal once Canterwood comes out. When it does, the 3.06G should become $150-200 cheaper, and the R9700 should be cheaper as well, so...
Ok, after a little research, I came up with:
3.06Ghz P4 w/ HT $547
ASUS P4G8X $195
CORSAIR DDR333 TWINX (512MB) $150
R9700 PRO $271
Western Digital 120Gb 7200rpm HDD $120
LiteOn 16x DVD-ROM $35
So, from these specs alone (from pricewatch.com), you should be looking at a $1350 or so price tag, if I´m not mistaken, plus, of course, case and power supply (and possibly monitor, keyboard and mouse if you haven´t got those yet). It´s hard to predict how the price will go down, but i´d estimate that it´ll drop about ~300-350 or something until July. (is that too much? what do you guys think?)
Oh, and by the way, this looks like one hell of a system to me!
And I should also agree with Hardwareboss. If you do wait until july, then get your hands on a Canterwood mobo. It´ll be upgradeable as hell for years to come and is a killer mobo in specs. Shouldn´t even be that much more expensive - and certainly worth it!