To make a withdrawal request, login to your Stars Account and visit the Cashier.Select the 'Withdrawal' button and input the amount you'd like to withdraw, then choose 'Submit'. Review the on-screen information carefully before you complete your withdrawal request.
The PokerStars website is available in the United States, but only players in a handful of states can access the real money games listed there. This isn't because PokerStars doesn't want you at the tables. The poker site is active in almost all the US states that have legalized online poker.