Hello collegue GPS tracker builder. I also experienced problems in finding a phone to (likely) work for the European frequencies. The Motorola C168
i phone is also available in a model for the European frequncies. This model is called the C168 (without the i).
Such a model might be obtained from places like India.
Here is a direct link to an auction site which might help you get such a model.
Mike has tested such a phone for me as far as possible and this should work. I'm currently building the tracker myself so I can hope to inform you about the results.
http://auctions.rediff.com/search.php?q=c168&x=33&y=6