Heavy-Duty 3-Foot Tripod Mount
$29.99
Model: 15-517
Catalog #: 15-517
from radioshack.com. Usually the stores carry one or two. Do a search on that model number or just type in "antenna tripod".
Next, goto homedepot and get some PVC pipe. I forget the correct diameter, but you could bring your dish with you and make sure. Get a 10' piece and then cut it down to however tall you want it. I believe mine is about 5'.
I've used this setup tons of times at tailgates. It has worked both with a dish300 and a 500. I usually bring some pieces of wood to level the tripod.
Oh, and dont forget a compass. Usually it is sunny and I can just plain eyeball where it should be pointed, but the last time we were out it was cloudy and took a while longer because it was a different stadium and I had no reference points to work with.