Poking around the boards, and I found:
http://chicago.straightdope.com/sdc20090409.php
The line for pictures and autographs starts over there. $5 gets you one of each, if you bring your own camera. 
I’m jealous!
Sweet! 
Did you get a rush when you found that?
Pshaw, that’s nothing. Cecil Adams once entered a thread simply to agree with me.
(Granted, the point he was agreeing with me on was “Cecil Adams is correct”, but, still…)
He knows all. He sees all. He is a cosmic love pulse matrix, fastly becoming a technicolour interpositive.
Hmmm. Autograph and picture sales are somewhat underwhelming thus far. C’mon, people—it’s all about the Lincolns, bay-bee. 
Bah. Come back after you’ve directed Cecil toward crucial empirical evidence involving penises (not for the faint-of-heart).