Server motherboards do seem awfully expensive, but of course you get what you pay for. I for one (and I'm sure plenty of others) have been getting on OK with "normal" motherboards (although my core motherboard did fry the other week.... ahem). Personally I would definitely consider getting a server motherboard in the future, if only because Thom has recommended it... the difference is that I have been playing with LMCE for several years, and have fully accepted it into my life! Maybe you do not want to spend that much of your hard-earned to begin with.
Now you've narrowed it down a bit (we're going with full ATX right?), maybe have another look at the wiki, keep newegg open on another tab, and see what's available. I would say that ASUS or Gigabit were reasonable brands. Post back with some motherboards that you like the look of. One thing I had to keep in mind when buying a full ATX mobo was the number of PCI slots vs PCIe slots. I needed at least 3 PCI slots (two tuners and once NIC). You might want to consider this also, as it keeps more options open to you in the future.