The following are address's that you can write to him!:

Adam Sandler 
5420 Worster Ave 
Van Nuys, CA 91401 

Adam Sandler (adam's agents) 
c/o Baker-Winouker-Ryder 
9100 Wilshire Blvd. 6th Floor 
Beverly Hills, CA 90212 

Endeavor (autographed picture) 
9701 Wilshire Blvd. 
10th Floor 
Beverly Hills, CA 90212