Just posting a few of my favorite websites. Don't mind me.
pipl.com - Enter a name to get the person's certifications, job history, birth records, arrest logs, etcetera. Enter a phone number to get those names. Enter an email to find their various web profiles. Enter a Username to see if that person's anywhere else on the web.
whitepages.com - Enter a name to get tons of dirt about the person's home, family, neighborhood, etcetera. Enter a phone number to get those names.
spokeo.com - Enter a name to get tons of dirt about the person's home, family, neighborhood, etcetera. Enter an email to see where that email's been. Enter a phone number to get censored information about who owns the number.
tineye.com - Might be able to find duplicate entries of images across the web.
regex.info/exif.cgi - If the picture is fresh from a device, this site can get you information on that device.
Google.com - Find whatever you missed.