You could ask your local school music teachers for references. You could also check your phone book and see if there are any instructional studios (vocal, dance, instruments) in the area. Before I started taking lessons at one I had no idea these even existed, but there seem to be a few in my area.
Or hit up jazz bassists in the local clubs for references.
Also, you can search for teachers right here at Talkbass.
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I did a member search here and 6 members are listed as available for instruction in PA. Not being from PA however I don't know how close any of those people are to you.
To do this search, click "Members List" at the top of a Talkbass page. Click "Search Members", then click "Advanced Search". On the next page, scroll down until you find the "Available for instruction:" field. Then click the drop-down, select "Pennsylvania". Lastly, click the "Search Now" button on the bottom of the page. This will bring back the list of 6 members available for teaching in PA.
Hope this helps.
