Doing a search on google, it looks as though this technology is available, but the whole thing sounds rather dubious to me.
A phone can obviously be located by triangulating its position, but would this not require access to raw data from phone masts? Who is going to give joe public access to that?
Also, do the masts even record the data that would allow a phone to be triangulated?
Very curious to see whether this is true or not, and I would certainly be interested in such technology, or paying to access such technology, as every now and then I would like to check up on people throwing sickies from work