For help winning your auctions, go to the auction house at about 8pm. Buy anything you want, but make sure you go home and go to bed before 9pm. When you wake up the next day, all your items will be at the post office.
It is possible to change your hair. To do this, speak to Leslie. Click the bubble in front of her asking if you want to change your hair and you will be able to cycle through the possibilities until you find one you like.