This is the last part in the series, I promise! If you haven't done so already, I recommend you read parts one, two, three, four and five first.
In the previous 5 parts I have set out a rough guideline for how to introduce open source software into your church. Unfortunately, most of the time you won't be able to go all the way to a total open source setup, so be prepared for that. It will most likely take a few years to make headway beyond getting your pastor to use Firefox or Chrome.
The easiest way to introduce new software and IT systems would be if you are the IT director, or in some other position of influence in your church. Sadly, the fact of the matter is that if you don't have some sort of clout in your church, no one is going to listen to you. In most churches, getting into a position of influence takes a few years, so you'll need to have perseverence and a willingness to play a large role in helping out in your church.
If you are successful in converting your church to OSS, please let everyone know about it, especially us here at Christians in Open Source Software. Make sure you blog about it. We would love to hear about how your church is using open source software.