Here are some ideas (all prices from Newegg except where noted)
Antec Performance Plus 1080AMG mid tower w/430w PS- $118.99
MSI K7D Master-L Dual AMD CPU motherboard: $195
2 AMD Athlon MP 2400+ CPUs- $158 x2, $316
4x Kingston 512MB PC2100 ECC Reg. DDR- $99 x4, $396
ATi (Built By ATi) Radeon 9800 Pro 128mb- $389
2x 120GB/8MB 7200RPM Maxtor IDE hard drives- $113 x2, $226
2x Thermalright SLK-800A heatsinks- $37.99 x2, $75.98
7x Enermax Adjustable 80mm fans- $5.99 x7, $41.93
2x Antec "Cobra Cable" A26 rounded ATA-133 cables- $12.95 x2, $25.90
Antec "Cobra Cable" F16 rounded floppy cable- $8.99
Total- $1793.77
If you wanted to go with a single-p4 system instead, I'd get:
Antec Performance Plus 1080AMG mid tower w/430w PS- $118.99
Gigabyte GA-8KNXP (first P4 board I've ever seen that I REALLY want)- $227
Retail Box 3.0GHz/800MHz P4- $417
6x Corsair 512MB PC3200 Value Select DDR RAM- $79 x6, $474
ATi (Built By ATi) Radeon 9800 Pro 128mb- $389
2x 120GB/8MB 7200RPM Maxtor IDE hard drives- $113 x2, $226
Thermalright SLK-900U heatsink- $46.99
5x Enermax Adjustable 80mm fans- $5.99 x5, $29.95
Enermax Adjustable 92mm fan (for SLK-900)- $6.45
4x Antec "Cobra Cable" A26 Rounded ATA-133 cables- $12.95 x2, $51.80
Antec "Cobra Cable" F16 rounded floppy cable- $8.99
Total- $1996.17
Or you could go with a single AMD system:
Antec Performance Plus 1080AMG mid tower w/430w PS- $118.99
ASUS A7N8X-Deluxe motherboard: $127.99
AMD Athlon XP 3200+ Retail CPU- $452
3x Corsair 512MB PC3200 Value Select DDR RAM- $79 x3- $237
ATi (Built By ATi) Radeon 9800 Pro 128mb- $389
2x 120GB/8MB 7200RPM Maxtor IDE hard drives- $113 x2, $226
Thermalright SLK-800A heatsink- $37.99
6x Enermax Adjustable 80mm fans- $5.99 x6, $35.94
2x Antec "Cobra Cable" A26 rounded ATA-133 cables- $12.95 x2, $25.90
Antec "Cobra Cable" F16 rounded floppy cable- $8.99
Total- $1659.80
The Dual AMD system will be easily faster than either of the single cpu systems, probably by a factor of 1.5 or more... however, that Gigabyte board (especially the Ultra version) is soooooo nice... IDE RAID, SATA, U320 SCSI 6-phase power regulation, 6 DDR slots... ooh, I want one... that board is enough to make me really want a p4...
The Athlon 3200 system would be about as fast as the P4, and it's $300 cheaper... but any of those would be outstanding systems for just about everything- DV, photoshop, games, whatever... oh, by the way... you won't need that SB Live if you get the A7N8X-Deluxe... the onboard audio on it is better than the SB's audio...