The general rule is you must collect state sales tax for any state in which you have a business presence. Therefore I collect tax for orders where the customer address is in NC because I have a business presence in NC. You can configure PayPal and Google to collect tax for you based on the state, you must tell them the tax percentage which can often be a little tricky to find out and typically may vary by county. like here in NC there is a base tax rate for the state but counties also charge tax so I had to find out the tax rate for the county where I operate and use that in my google and PayPal settings.
Note that google and paypal only collect the tax based on the settings you provide, they don't pay the tax or forward it to the states so it is up to you to find out how to report it/pay it to your state/county.
Hope that helps,
Joe