The term 'hyperhydrosis' leaps to mind here. It simply means that your feet are probably more prone to profuse sweating than those of Mr or Mrs Average.
Your local chemist's shop will stock everything from special insoles through to antipersperants specifically for feet. Further more, there's a person behind the counter who's better trained and qualified than any doctor to deal with such problems - the pharmacist. Ask to speak directly to him/her and he/she should be able to recommend something to solve all your problems.
Chris.