“I reside in Arizona my wife resides in Oklahoma with our two kids. I want to file for divorce, is this possible with us living in different states and how will the custody/visitation be decided?”

You surely can file for divorce. Most states would allow for either spouse to file where they have established residency. She might try to change venue. She might have an argument to have issues about the children decided where the children are found (Oklahoma). However, if you serve her papers, and she responds in that Court, then the Court will have continuing jurisdiction to hear the matter.