As a musician and hardware enthusiast myself, I have to reply to two things that were stated above about AMD and SoundBlaster.
I have chosen the SB Audigy and I have no complaints. Going as far as saying that Soundblaster for audio editing and mixing is "sacrilege", is SILLY. 24-bit, 96kHz digital-to-analog converters and 100 dB signal-to-noise ratio is high quality. What was previously stated is like saying that a shirt bought at Target will not cover your back as well as a Hilfiger or Ralph Lauren because you paid less. Pretentious BS, that's what I say.
http://www.homerecording.com is for just that--"semi-pro's". Go to
http://www.sweetwater.com for professional gear and software. But then take a look at the ridiculous prices for some of the sound cards they carry. Compare specs with the SB Audigy. Hmmm...
There is also no technical reason that can be given for why an AMD CPU would cause "hiccups," as opposed to an Intel CPU. If someone can offer one, I would love to hear it. If anything, that would be a chipset issue. If you go with a VIA chipset motherboard, go with the KT266A chipset. It's the most up-to-date and most mature for DDR SDRAM. If you are hesitant about VIA, get the AMD 760. It's a little slower, but very stable.
Get a lot of memory and a LOT of HDD space. Multi-track audio takes up a sh*tload of storage space.
Get a fast burner. I've heard that TDK is about to launch a 32x CDR that can store 2.1 GB on a CD-R (cheap media!), and that will cost about $199 USD on launch. Pretty cool, if you ask me. Or you might want to wait till DVD-R is a bit cheaper/faster, up to you.
If you want more processing power and money is not really an issue, consider the Tyan Thunder or Tiger (AMD 762MPX chipset) or the MSI K7D (my recommendation) and run two Athon XP's on a dually set-up(and yes, XPs *will* work just like the MPs). The MSI K7D is starting to appear at retailers and is ATX form factor (which is key). It has an onboard networking adapter and also has two 64-bit PCI slots in case you do go for an extremely high-end audio card.
Also consider getting a video card that will support two monitors. Most audio editing software takes up a lot of screen space. The only Nvidia card that has dual monitor support (Twinview) is the Geforce2 MX 400. But if you go with that card, you'll be screwed in the gaming department, but you're in it more for the music than you are for gaming. You might have to consider an ATI card if you want dual monitors and relatively fast gaming.
If you get the Soundblaster Audigy Platinum, don't expect the bundled *software* to be any good, because it's not good for recording by any measure. The digital sound processing is kinda' sketchy too. Go to sweetwater.com and look at their mixing and recording software, but I'm sure you already know about software since you were only asking about a MoBo and CPU.
On the Audigy Pt drive, the front 5.25 drive is great and has a front MIDI port, S/PDIF in/out (good if you use Sony Minidisc), and RCA inputs. It comes with a remote control too. Another cool thing that I found is that the Audigy has a port where you can plug in an electric guitar (standard lead) and use that as an interface to your PC. Sweetwater sells a similar, separate MIDI interface by Korg for about $300.