You're all over the place lol.
I'm not a computer guy but... I can try to help a little.
LGA 2011 > LGA 1155. It's the latest socket type for Intel, and it holds the most powerful CPUs. Compare an Intel i7 3930K to an i7 3770K.. it's no comparison, the 3930K smokes it. BUT... that doesn't mean the 3770K is useless! It's still a great processor and could be all anybody really needs depending on what their production/mixing needs are. The same can be said for AMD stuff. THe AMD FX 8350 is said to be very very good and can hang with some of the Intel CPUs. THe AMD FX8350 > AMD Phenom II any day. BUT... that doesn't mean the Phenom II is useless! It's still a great processor. I use one right now and I can technically get any work done that I need... since you can always bounce audio once your project starts to get huge and complex.
So.. I hope that explains your socket question a little bit. The LGA 2011 chips are the latest.. but that doesn't mean the LGA 1155 chips are garbage. It just means they are not the newest. But.. 2nd place in the "super chip" race can still mean 1st place in the "music production chip" race. Get it?
In regards to firewire... most audio interfaces recommend getting one with a Texas Instruments chipset. Most motherboards that include firewire may not necessarily have a Texas Instruments chipset. For that reason... a lot of people buy a PCI firewire card. There's a difference between PCI and PCI Express.. and i think there's a few variations of PCI Express. So make sure you buy the right one for your motherboard.
In regards to your motherboard question.... I don't think you can make a "bad choice" necessarily. The high end motherboards are usually for computer guys who do serious overclocking and are big gamers.. so they need multiple video cards and have a lot going on. For music guys... I honestly didn't notice any issues with my cheaper $60 mini-atx motherboard for my AMD phenom for all intensive purposes. I wouldn't worry about buying the "best motherboard for music". There is no best. Just get one that suits your needs and gets halfway decent reviews as at least a "good bang for back" from computer geeks and gamers. Pay attention to the maximum RAM it can support, how many RAM slots it has, the type of CPU it takes, and what types of PCI slots it has on it. Also pay attention to how many USB slots it has vs. how many you need.
In regards to the CPU debate.... Intel > AMD... almost at every price point. The AMD FX 8350 finally makes it interesting again. But... again.. Intel also means you're spending much more money on the CPU and Intel motherboards are more expensive. AMD does give you good bang for the buck overall and will get the job done for a reasonable cost. I would say if you have the money... get an Intel setup, but if you're on a shoestring budget... you can be very happy with an AMD based setup. I just build my friend an AMD system for around $300.... very nice, modest setup that he can use for a fairly long time unless software programs start demanding much much more, which usually starts to happen.
The last thing i'll add is consider getting an SSD for your system drive on your computer... and another one as a "sample playback" drive if you can afford it. The speed is ridiculous. Once you get one... you'll understand lol... you won't want to go back to a regular HD.. the speed of boot and program load is very spoiling... and if you get one for your samples/sample libraries.. you will be very happy when your Kontakt instrument loads in 2 seconds instead of 14 seconds. It can be a mojo killer.
Is Intel i7 necessary? Depends on what you're doing. If you're mixing music and you have 4-5 effects on 30 channels of audio.. yeah, you may want an i7 under the hood. (There are several different types of i7, i5, and i3... not all i7's are created equal as I kind of alluded to above). But if you're only recording guitar and playing 2-3 VSTs, and outsourcing your mixing to an engineer.. or just using a few plugins here or there to mix... then maybe the i5 will suit you fine. The i3 probably isn't worth buying lol. No point in going that low.
24GB of ram? depends.... how large are your sample libraries? And... does your DAW have a 64bit version? Assuming it does... 24GB is a lot..... i'm currently happy w/ 16GB, i only come close to maxing when i have 5-6 heavy sessions loaded at once. However.... one trilian patch can be 1-2GB right there. So... again, it depends on your needs. if you don't have huge patches... 8GB should be fine. you can always upgrade later.
lastly... i say all of this assuming that you're building your own computer of course, which is usually cheaper and better.
---------- Post added at 08:39 PM ---------- Previous post was at 08:34 PM ----------
Also.. i forgot..
PassMark Intel vs AMD CPU Benchmarks - High End
^Go here. This will help you visualize the performance of the CPU you're considering and how it compares to others. The higher the score, the better. And you will see all of the different CPUs available past & present. (And you'll see what I mean about how there's several different i7's and i5's, etc)
Good eeeeehhhvening errbody 
ive spent a ton of hours searching for a good mobo and man its hard 