"stuffing" list of city/States with stuffing ???

Hi

we are US based and are providing a services in all 50 states.I see quite many searches on google look like : "our service" California or "our service" San Antonio.

I would like to add on our page the keywords of all US states and all main cities but without being penalized by google.

Is there a smart way ?

we use joomla.

Thank you

You should create a page for each state and city you want to rank in.