In the "hat-box" tucked under Grandma's sofa? ;-)
Seriously, you have to be careful about going out to "find" old photos and posting them on your wikiprofiles. If you find them on another website, they most likely belong to that website or the person who put them there, and you can't just copy them for use here without their permission.
Therefore, although I was joking with my opening comment, I really wasn't... The absolute best place for old family photos is from old family. Snap a picture of the photo with your digital cam, take some notes about who, what, when, and where, and you'll have a far better end result than anything you can "find" currently online.
Good Luck! And welcome to WikiTree!
-P Rich