The shipping charge will only occur when you get to the confirm page. If you are choosing to pay with PayPal on the checkout form you will not see the shipping charge until you get to the pp_confirm page after logging in to PayPal.
How are you specifying CA as the state? You must have it recorded in your globals file under the tax section. Once you have done that you must enter the state for the checkout. If you using PayPal you will not see this charge until after you return to the pp_confirm page.
So long as the value you enter in the globals file matches what the user has for their info on the confirm page the tax should be applied like the decimal value you have entered into the globals file.
// Tax Setting
$WAGLOBAL_TaxRate = 0.08;
$WAGLOBAL_TaxState = "CA";
This should give you a tax charge of 8% for users that specify CA as the state. Let us know if you have it setup like this and still do not get the tax charge and we will look into this further with you.