Hybrid Theory EP
In The End (Live & Rare) -not sure if it counted as an EP
Collision Course
Live in SoHo
Songs From The Underground
Decade Underground
2011 North American Tour EP
iTunes Festival: London 2011
Burn It Down EP
Burn It Down Remixes -not sure if officially released
A Light That Never Comes EP
Also I think there was a The Catalyst Remixes EP too, not sure about that. You could add Xero. And don;t know whether Download to Donate were EPs or albums