Чегой-то is a written contraction from "чего это" as it sounds like that (чивойта). Something a kind of written "wanna" where it's "want to" in fact. This contraction in literature looks like an attempt to imitate words of someone who is "rural", "redneckish" or something like that. Otherwise it looks like the author who wrote that is either rural or redneck or pretends to be so.

Чего это not only means "what is it" but also can mean "why".