You will have an almost identical system to mine if that is what you get. A couple of things... I am with the previous post, the Klipsch 4.1 are notorious for amp burnouts. I would go the logitech route as well. Speaking from experience here and handling Klipsch RMA claims from a local Retail outlet. I would go the Corsair route myself, as you have considered as well as the ABIT boards have proven to love the Corsair chips particularly. But yes, stay away from the less performing versions as you seem to have a handle on that. For speed, I would add the Raptor drives to that board. I have a RAID Stripe of two Raptor drives and they smoke. My 120GB WD drives take a clear back seat to the Raptors. The network card (who cares much about this decision really). The CSA gigabit of the IC7-G is nice, but not neccessary as you may already have decided. My 2.6 easily gets me to 3.25 but the chip I use is an "ES" model so you should surely get more out of your 2.6C. I would seriously consider DDR 500 memory by the way with this config. It will help you in OC'ing without the free multiplier. That way you can still try to run decent memory ratios. Even with DDR 500 running 1:1 ratio you can only OC to 3250MHz. If you ask me, I would go for the 2.8C (Still not too expensive, yet only a little bit more than 2.6C costs. You will get the 14 multiplier instead of 13, so you can go 250 X 14 and get 3500 with DDR 500 at 1:1 ratio. Assuming that 500 will do something like 515DDR, which isnt unheard of, you can get your magical 3.6GHz number you are aiming for. So I would say get :
Intel 2.8C (add 50 bucks)
Abit IC7
Corsair DDR500 or equivalent (This will add 160 bucks for DDR500 1GB versus DDR400 1GB)
WD Raptor (only one if you have to and you can add one later to stripe) (for speed of course, you may want storage)
FX5900 or 9800 (I would go Nvidia, but just personal preference, either card is going to rock)
Logitech Z680's (but z560's would still be great)
Everything else is kind of in the air... Your choices are fine.
I cannot tell you how close that system description is to mine though, it is almost uncanny. I am even using my previous SB Live! from the last machine as well and the same case.