weekends...makes one lazy to do things, especially check posts, so I apologize for not being more helpful
price is good, but check around other "retail" online merchants. Tigerdirect functions too much like brick and mortar rather than a true online store. I think you can escape their state taxation though, though I haven't checked where they apply. Shipping is standard retail shipping, which isn't all that bad but could be better.
When it comes to components like RAM and CPUs, try not to look at auction sites, unless you're shopping for used parts. For example, gauging the e6600, it might cost wholesalers, system builders and the like $289 (but I haven't checked, just guessing). Comparing with legitimate online merchants, you can then determine if a risky and often time shady ebay transaction is worth it.
If you've bid, just good luck and I'm hoping you'll be satisfied.
as far as mobos, there are many ways to go. I can easily recommend what I bought, the intel d975xbx...but you could save depending. The intel d975, aka Badaxe, is a top tier mobo. Has all that you are looking for BUT, also gauge for yourself what gpu set up you want.
because of the gpu you bought, the badaxe might fit you perfectly because of it's xfire design, but does also have onboard audio (which btw I believe compares well to the xfi - creative is way overrated