you can always look for Jeet Kun Do which is all about "no style"
but the majority of what was said so far is true. take your karate, your muay thai, your kung fu... then incorporate your hung gar, your krav maga, your bagua zhang, your sambo, your pankration, your ninjutsu, your lau, your extreme monkey combat...
hell if you really feel bold, try adding kali and kenjutsu.... i think there's a website dedicated to the moves of gun-kata too.
Carley Simon, thanks for writing that song about me!