Evangelists
Choosing your events is directly tied to choosing your evangelist. Certainly you want an evangelist who is appealing and has the ability to communicate with your target audience.
When choosing a speaker, most importantly consider this: the Bible tells us that some have been given the gift of evangelism. It's a spiritual gift. They aren't just skilled preachers with good people skills. They are gifted by God with a divine endowment to lead people to Christ. That's the kind of person you want. Not just someone who doesn't cost much, nor someone who is charismatic and can preach.
Bringing in an evangelist to be the main speaker at your events costs money: you would likely need to cover travel expenses, food and lodging, an honorarium and any other incidental expenses. But don't let that deter you from bringing in a guest speaker, especially one with training and experience in Affinity Evangelism (AE).
Small churches attempting to minimize costs might naturally think to use their pastor. He or she would love the opportunity to interact with the unchurched, and more importantly, they come cheaply. But there are very real pro's and con's to having your pastor as the evangelist.
One low budget option with a lot of power is to utilize the testimony of local people. Who do you know? A cancer survivor whose faith in Christ gave them the strength to get through. An addict whose higher power, Jesus, got him/her sober. A couple whose dead marriage had Jesus breathe new life in it. A business person who has survived difficult experiences and faith got them through. Let them tell their story during the event and give witness to Christ's power in their life. In some cases they will be quite capable of telling their story and calling people to make a decision to follow Christ. In other cases, the pastor or another person might finish sharing the Gospel.
Here are some places you can find an evangelists.
Proclamation Evangelist Network
Luis Palau - Next Generation Alliance
Or look in the side bar of this blog.