Help with configuring Tax by State

I'm have difficulty applying tax to purchases with a billing address of California. Here are my settings, and when I attempt to pay with a California billing address (both as a registered and non-registered user) tax is not applied.
Tax Settings:
Prices include tax:Null     
Allow customers to select tax display type: Null   
Tax display type: Excluding Tax
Display tax suffix: Null
Display all applied tax rates:Null   
Hide zero tax:Null   
Hide tax in order summary:Null   
Tax based on: Billing Address  
Default Country: United States  
Default State / Province: California  
Default Zip / Postal code: [blank]  
Shipping is taxable: Null
Payment method additional fee is taxable:Null   
EU VAT enabled:Null

Tax Provider Settings: Tax by Country and State
Configuration:Country: United States
State: California
Zip: *
Tax Category: Your Tax Class
Percentage: 9.7500

Thanks for your help!