Where/how can I look up laws with all current changes? I need to find civil law in Pennsylvania.?

Is there a website, or are there websites in states and/or counties? Or can I go to a law library and look up laws with all current updates/changes? If so, can someone tell me how to do this - go to a law library and look up the laws? (I'm not a lawyer or a law student, and I'm guessing there is an effective method of researching current laws.) Thank you!