Too many to list lol. When practicing, I'm pretty much always learning songs that use a lot of the techniques I'm trying to get better at. For me, I'm a metal head, and Metallica, plus Megadeth, are my main draws. I'm currently learning Master of Puppets. I was originally working on Symphony of Destruction by Megadeth but I couldn't figure out the 4th measure of Marty Friedman's solo for the life of me, so I took a break. Now I'm trying to get my down-picking up to par. Yeah, I'm gonna do it like James Hetfield and play all of MoP using only downstrokes
My other all time favorite bands/artists that I also draw inspiration from would have to be: Judas Priest, Iron Maiden, Scorpions, Racer X, Dream Theater, Slayer, Periphery, Meshuggah, Opeth, Slipknot, Stone Sour, All That Remains, Killswitch Engage, As I Lay Dying, Vivaldi, Bach, Beethoven, Jimi Hendrix, Paul Gilbert, etc, etc. Basically the whole nine yards.
Are you my long lost twin? James Hetfield is one of my personal idols both as a musician and as a person.
Anyhow onto the inspiration. I love music in all it's forms but if I could only pick a single genre for what inspires me the most probably metal. But here's a list of bands and artists that really have ab ig influence on waht I try and sound like.
Voltaire
Iron Maiden -especially Adrian Smith's work-
Metallica
Megadeth
Two Steps From Hell
Audiomachine
Flogging Molly
Meatloaf
Black Sabbath
Dio
S.O.A.D.
Stefan Elmgren -former guitarist in a band called Hammerfall-
Joe Satriani
Ted Nugent -as a guitarist not as a song writer or the band though I do love Fred bear-
Tartanic
John Williams
Nightwish
European Folk Music, especially Celtic