Andrew Loomis is first and formost the genius whose books taught me to draw. If it hadn't been for those books, given to me by my grandfather when I was six, I may not have the style or skills that I have now.
Major inspirations for illustration include Maurice Sendak, Brian Froud, H.R. Giger, the work of Oliver Postgate,
Lorenzo Mattotti, Simone Rea, Sam Weber, Alessndro Gottardo (Shout), Yuko Shimizu, Chris Buzelli,...
Andy Warhol, Magritte and Saul Steinberg
akihiro yamada, mucha, takato yamamoto
Mine Yoshizaki, Masashi Kishimoto, Doug TenNapel, Maurice Sendak, and Dr. Seuss come to mind.
I love the work of so many people, and I'll try to name a few: Tomer Hanuka, Asaf Hanuka, Ping Zhu, Jessica Walsh, Craig & Karl, Jesse Auersalo, Sac Magique (all illustrators represented by Pekka really)
Tove Jansson, Edward Gorey, Jan Lööf, Gary Baseman, Jack Teagle, Saddo Raul... That's just a couple on the top of my head!
Lisolette Watkins, Sara Fanelli, Lauren Child, Brooke Weber, Peggy Wolf but to name a few.