Ah, alright so lube is the answer. I think I used some Tenacious Oil before on my road bike, but the quiet didn't last long (like 10 miles). Maybe the chain had some junk in it, even though it was a brand new Shimano chain.
In response to GirlAnachronism, you're right that I'm worrying too much about certain details, but the quietness of fixed gears is one of the main reasons I want to build one. So I want to get the right components before I find out that I've wasted $50 on a chain, or even worse $150 on a 1/8" drivetrain.
As for the chains, I'm thinking I might get a KMC, and the blue colored one interests me, but I can't seem to find it in 3/32". Anyone have any resources?