Here are a few other websites that have great resources!
Pennsylvania Historical & Museum Commission: Pennsylvania's historical commission provides access to many different researching tools. There are digital collections, free access to Pennsylvania state records through ancestry.com Pennsylvania, and research guides. www.phmc.pa.gov
PHMC Historic Marker Program: The Pennsylvania Historical & Museum Commission also has a searchable database for their Historic Marker program! share.phmc.pa.gov/markers
Pennsylvania State Archives: The Pennsylvania State Archives collects, preserves and makes available for study the permanently-valuable public records of the Commonwealth, with particular attention given to the records of state government. The State Archives also collects papers of private citizens and organizations relevant to Pennsylvania history. www.phmc.pa.gov/Archives
National Archives: While most of their collection is still available for in-person researching only, there are still many resources available, including catalog searching and other researching tools. See all the resources available at archives.gov/research
Library of Congress: The largest library in the world! Located in Washington D.C., the Library of Congress also offers a large collection that can be viewed online. www.loc.gov
Find-A-Grave: This external web resources is free, and allows visitors to search the largest collection of gravesites. Records include gravesite location, dates, family members, and some include pictures of the gravesites. findagrave.com