AVA is a good outfit, good reputation... Another is Puget Systems.
I'm alittle concerned about some about some of the advice; you should stay with socket 2011 for your intended use. Socket 1155 is great for "enthusiast" use, gaming, etc - but the problem with that platform is memory access:
Socket 1155 uses an external onboard memory controller - meaning all memory access from the CPU is limited by the capabilities of your chipset. Performance gains can only be had using very fast, low latency modules, with direct tradeoffs of performance vs: stability.
Socket 2011 uses an on die (ie on the CPU itself) memory controller, bypassing any chipset memory controllers. If you look at memory placement on 2011 boards, you'll notice how memory modules are tightly clustered arounbd the CPU. In addition, memory access is interleaved - in the case of this platform, you populate memory in 4's, each module is addressed in round robin fashion. This reduces the effect low latency memory has on overall performance, allowing you to choose less expensive, higher stability modules. I would highly recommend choosing a mainboard with 8 available modules vs: the more common 4 module boards.....
A lot of advice appears to be based on Newegg searches - thats great, but be aware they will sell anybody, anything, whether a "collection" of parts is appropriate or even compatible is of no concern to them - if you look at reviews, you can plainly see this. I'm an Intel channel partner and obviously have a preference toward their mainboards (their engineering support is magnificent) - in the case of the model I pointed out, every negative review was posted by someone who neither understood or applied the relevant BIOS patch, and downloaded the correct drivers......
Finally, you posted that you intend on using Adobe Premiere; this will decide your video card selection, as Premiere's Mercury rendering engine will only utilize nVidia GPU's. Premiere officially supports only "workstation" class cards, but by altering %sysvol%\Program Files\Adobe\Adobe Premiere Pro CS6\cuda_supported_cards.txt many desktop class video cards can be effectively used.
Studio 1 Productions has a fascinating article exploring this with some suprising results in testing:http://www.studio1productions.com/Articles/PremiereCS5.htm
Let us know what you decide!