I can't post any specific market stats (as we spend a lot of money to get them) but I can say you will need an exceptional marketing plan to sell hard drive portables to females 18-35. The market is strongly weighted to males (which I guess is the point of your assignment).

Right now I believe Apple and Creative have the HDD market sewn up between them, with Rio, Archos and miscellaneous vendors making a dent also. Rio has #1 market share in Flash and CD and plans to address the shortcoming in HDD this year.

If you come up with a great plan to sell to a significant number of female consumers, let me know

Rob