Iron Maiden and Killers signed by Paul Di'Anno.
Mastodon 09 tour poster signed by the whole band.
Rules of Hell boxset signed by all members of Heaven and Hell.
United Abominations signed by the whole band.
The last two items I didn't get signed in person though.
5/4 - Rob Zombie
5/11 - Ghost
5/13 - Mastodon / Gojira
5/21 - Primus
6/28 - Iron Maiden - Bergen, Norway
7/1 - Iron Maiden - Luxembourg