If you live near a Microcenter they have them. Also if you look at 'all' the bundle combos on Newegg you can get the i7 3820 with a $20 item.
That is an unusual question. Any mother board that uses an Intel CPU, is an Intel-only CPU compatible board, and uses the Intel chipset required by that platform's CPU. The chipset is one of and usually is the most expensive single device/chip on a board (except the CPU.) No one else makes chipsets for use with Intel CPUs except Intel, and mother board manufactures must buy them from Intel. Every mother board sold that uses an Intel CPU means money for Intel, whether or not Intel made the board. The more boards sold that need Intel CPUs, the more money Intel makes.
Intel sends any mother board manufacture that requests it, the "engineering samples" of new CPUs and chipsets long before the CPUs are available to the public. That way, they can design and build new boards before the CPUs are released, so they are ready when the CPUs are on sale. The other mother board manufactures are Intel's customers first, and as their competitors, a distant second.
Newegg's mother board return policy is the same for all board manufactures. Yes, the ever changing prices and deals can be frustrating.
I bought a NEWEGG (CYBERPOWERPC) BUNDLE. it was packaged with an ASROCK EXTREME4. This is an X79 board. The only issue I have is that the bios was incompatible (according to ASROCK) for use with the new 3820. It required an upgrade to v1.6. They recommended upgrading to v1.7 as that was available. So far, all appears solid.