How to connect PC to TV with sound please help!

Alright, so normally I'm a pretty tech savvy guy, but this one has me a little stumped.

This is how it goes, I have a gaming pc as my desktop in my room, and recently I added a 32" HDTV with an HDMI port to my room to the right of my pc.

Now, it is within a few feet of the PC, and I was thinking of setting up my computer with the TV as WELL as my monitor, switching it to the TV when I wanted to watch movies on the bigger screen, but back to my desktop for normal browsing etc.

Now here's my dilemma. I can get a DVI to HDMI cable, providing video at ease, but as for audio? That's where it gets tricky.
Obviously I have to have separate audio coming from the pc to the TV, because my video card wouldn't supply that.

So here's my specs PC wise:
Processor: Intel E6600 @ 3.00 GHz
RAM: 2GB G-Skill
Video Cards: 2x Nvidia 9600GT in SLi
Sound Card: Creative XFI XtremeMusic (yeah the older one.)
Motherboard: XFX 680i LT Sli
Windows XP Professional SP2

There's the basics. Now, here is what I want to do, and hopefully you can help me.

I want to have it so I can somewhat easily switch between using my pc by itself with my speakers, to switching over to the TV to watch movies, without having to disconnect/reconnect cables all the time.
I know that video wise it shouldn't be a problem because of the fact Nvidia's software panel allows you to switch between displays pretty seamlessly.
But as for audio, I figured I could just turn off my speakers on the PC, and have the audio cables connected to my TV.
Now I already have a splitter to convert a 3.5mm headphone jack into the red and white cables (forgive me for loose terminology,) but I will probably need another one to split the signal between two different sides right? Like one for my speakers, the other for my TV?
On my TV the HDMI slot has an audio in (red and white) underneath it, so that should be okay.

I guess what I'm trying to ask here, is what all I will need to set this up, and if it's worth all the trouble. The primary use will be to watch HD movies from my PC onto my TV, or streaming things from Hulu etc.

Thanks and please let me know if I'm leaving any important info out!

-Collin