This is only a few hours of work. SqG (a pet project I did a few years ago) already does the GPS interfacing for your client side, and I am not sure how fancy you want to go on your linux server side, let's assume for now we go minimalistic.
How about this. I dig out the sources for SqG, make a trial version for you (say, a time-limited binary), you look at it and then we talk about more details.