This may not help much but I heard or read (and now I can't remember where) that as far as IQ is concerned, the men tend to cluster more at either end of the scale while women cluster more in the middle - which would make more male geniuses but conversely more mentally challenged males too....evening it all out to some degree, I suppose?
But it seems to me there is a measure of controversy concerning how IQ testing is done with the argument that white MALE culture predominants the testing subject matter, therefore giving that segment of the population an advantage. I was impressed when researching the "universal" genius topic online recently (universal genius scores off the charts in every catagory equally whereas most gifted are gifted in only certain areas like some savants are) that the only living one on record is a woman named Marilyn who is married to Dr Jarvik, the artificial heart inventor. So that blows a hole in the men are more gifted deal a little bit too, hmmm. History does show more documented male universals than female but that is just too easily dismissed by how during much of history men have been the cultural power and the historians both.
Maybe you need to modify or narrow your topic a bit to better reflect what the facts will back up, if that is possible. Its been pretty well established that men and women do think differently. Nowhere is it more evident than in processing spacial information, therefore making it biological that men tend to be better drivers than women. LOL
Perhaps if you reached the Mensa Society they could point you in a profitable direction. Look to see if they are listed in your phone directory. Bear in mind that not all "giftedness" is correlated to IQ - the arts, for example. Good luck in your research!
PS --
Look here too