Car not starting, need help diagnosing

[Loki]

First off, it's atrociously cold out, about 15 degrees around midday. I went out this morning and the car started right up and seemed to handle fine. I got to class and the car sat for 4 hours. When I tried starting again I got nothing. The starter kicks in and I get the old whirr-whirr-whirr but it doesn't turn over. The battery has to be fine as I had it tested a month or two ago, and it is only a year and a half old. I tried cleaning and re-tightening the battery terminals, as well as jump starting.

My electricals seem fine, so I'm led to believe it's a fuel problem. I did get 3/4 of a tank yesterday, so I know I HAVE gas. I think I may have stirred up some water laying in the bottom of the tank this morning, and it froze in the fuel lines after I got to school. Does anyone have any suggestions? I put some fuel treatment in the tank for laughs and I have some starting fluid handy, but I'm not sure what good it will do.

[Warlock]

Is the starter engaging? Do you have spark? Fuel coming out the line of top of the intake mani? Check that stuff

[Loki]

Is there any easy way to go about doing that? The car is stuck at my school right now.

[Loki]

So I went back to class to try it again and it somehow started up. I'm stumped =/ I just hope it doesn't die on me again after class.

[squonk]

So I went back to class to try it again and it somehow started up. I'm stumped =/ I just hope it doesn't die on me again after class.

it's cold... 240s don't like the cold.