I live and work in CA. My employer deducted PA state taxes. How do I file my state taxes. Noresident for PA, but what about CA?

Yes, you are correct. 

If you did work in PA for a period while you were a California (CA) resident, then you will file the Nonresident PA for those earnings.  CA will give you a credit for taxes paid to another state on the same earnings. If you did not work in Pennsylvania (PA) you would file that nonresident return for a full refund of any state tax withholding.

State Returns - Assumes both states require income tax returns to be filed: Prepare the nonresident state first.

1. Report the wages earned in PA.
2. Report it on your resident state and receive credit for taxes paid to another state.
   1. TurboTax does this automatically if the nonresident state is prepared first.

Credit for taxes paid to another state is allowed by a resident state when the same income is being taxed to another state.  Your resident state does not want you to pay tax twice on the same income. The credit that is allowed will be the lesser of:

1. the tax liability actually charged by the nonresident state, OR
2. the tax liability that would have been charged by your resident state