Contact Silver Spring Township for a Trap/Neuter/Release voucher for feral cats. This voucher must be redeemed within 90 days of the date it was issued. An appointment is required to redeem the voucher.
You can also trap the cat yourself and contact local animal rescue organizations (i.e., Find Toby in PA findtobypa.org or Nobody's Cats Foundation nobodyscats.org.)
If the cat doesn't appear to be feral, you can file a found report with the Humane Society of Harrisburg, contact a local cat rescue, or have a vet scan for a microchip (free of charge).