eastern Pa, looking for agency

hi, i am in the process of searching for an adoption agency. i am looking to go through the state.. swan. they sent me a listing of agencies.. i called them all, and asked for information. a few talked to me on the phone, but most just are sending info. this is such a HUGE decision. can anyone tell me how they chose their agency? what criteria was used to narrow them down? and if you used an agency in pa, (swan related) could you let me know what one, and if you were happy with them? thank you for any and all info provided. lainey