I made a tutorial of a DIY GPS Logger. Total cost is about 50-60€ (60-70$) + 3D printing + some cables and 2 resistors. You can find it here: http://www.rbaseg.eu/
I did not know where to put it, GPS logger are a technical tool, aren't they ?
If there was any doubt I'm not selling anything here, it's a DIY thing completly open source. People can just follow the tutorial and by the parts wherever they want, I have no interest in any company involved.