lets say a friend of mine wanted to get excommunicated from as many churches as possible. Given wikipedias list of churches that excommunicate/disfellowship, who would i talk to at those respective churches and which ones would send him a letter or some kind of documentation that he has been excommunicated?
You generally can’t be excommunicated from a church unless at one time you were communicated with that church. In other words, churches don’t excommunicate random people on the street, they only excommunicate members of their church. So the Pope will only excommunicate you from the catholic church if you’re a catholic…and probably not even then, even if you worked really hard at it.
You’ve got to become a member of the Church in the first place in orsder to get excommunicated. That’ll take some work. Then you’ve got to become enough of as public nuisance to the Church to get them to go to the trouble and effort of excommunicating you. That’s a lot harder. Most churches really don’t bother. You have to make yourself truly obnoxious to get them out of their torpid state of tolerancve and decide that you really are beyond practical redemption.
Besides which, I’m not sure who goes to the trouble to excommunicate anyone anymore. The Catholics do, and so does the Mormon Church (The Church of Jesus Christ of Latter Day Saints). If you cause a big enough stir for one to officially throw you out, ity’s certain the other will notice and not oblige you in your quest to collect excommunication certificates.
Regarding the Roman Catholic Church, excommunication is often misunderstood. It is not being expelled from the church in the sense of losing your status as a “member.” As far as Roman Catholic theology and canonic law is concerned, excommunicated persons will remain members of the church, but they lose their right to participate in worship and receive sacraments. The excommunication can (and must, according to canonic law) be lifted as soon as the reason for which it has been decreed ends.
Besides, canonic law also knows some sort of automatic excommunication that does not have to be decreed by any sort of authority as a sanction. According to this doctrine, certain acts, such as physically attacking the pope, will result in automatic excommunications even if you’re never caught or convicted as guilty by any authorities. Any sacrament you receive in this state is worthless.
Well, have you excommunicated him already, for starters? 
Jehovah’s Witnesses also disfellowship (similar idea to excommunication).