Tanner has a Christmas special of 50% off for the BUGBase stuff, including a GPS module with a SiRF module inside of it. At $3.50, that’s the cheapest GPS you’ll ever find. The only obnoxious part is the Samtec connector on the back, but one could just blue-wire it to a different connector.
ARGH, stupid talk won’t let me upload the PDFs. I’ll figure out somewhere to put them.