The state is stored as:
$_SESSION["WASF_CheckoutWizard_Sharp_Default"]["state"]
You could add an ecart rule with the trigges:
Session variable exists: WASF_CheckoutWizard_Sharp_Default
AND
Custom Expression evaluates to true: $_SESSION['WASF_CheckoutWizard_Sharp_Default']['state'] == 'CA'
Then set the charge to:
Flat rate: 22
or whatever flat rate charge you want for that state. Then duplicate that rule for each state you ship to.
That session variable is updated to the value selected in paypal when using paypal checkout, so it will automatically update the charge. I've attached a screen shot of how the rule should look in the eCart object.