I always start at microcenter.com to narrow it down and read the reviews and then buy the product on amazon.com. I have had great success with MSI, ASUSROCK, and ASUS motherboards. First, pick what processor you want to use, THEN, start looking at motherboards. For Linux, essentially anything will work but look for high GHZ. Like a 3.5 GHZ dual core (Pentium D or Core II Duo) would be blazing fast for this purpose. And probably $35 US.
Just look at the pin out: LGA 1150, vs. LGA 1151, etc. Make sure you find a reasonably priced motherboard to match your processor. Then you just need RAM (4 gb would suffice but 8 would be optimal). I wish I could build it for you!