Watch the Wah-Wah online guitar lesson by Chris Buono from 60 Electric Guitar Techniques You MUST Know
It's safe to say a wah-wah pedal will be your first stompbox if it's not already. The wah is a sweepable fixed bandwidth filter that has a treadle you rock back and forth producing vowel-like inflections. The phrasing possibilities are only limited by the player. These days, you have an array of major as well as indie pedal builders who make incredible wah pedals such as Dunlop, Vox, Fulltone, Teese, Xotic, and Wilson Effects.
Looking for inspiration? How do you not start with a guy nicknamed Wah Wah Watson? Melvin Ragin has played a wah-wah pedal on a dizzying array of recordings since 1970, starting with The Jackson 5's "ABC". Ironically, W.W.W. did not play on "Shaft" - that was a guitar player named Charles "Skip" Pitts.