Sadly open air preachers have a bad reputation among the unbelieving public, and sadly even amongst many Christians, including many on this board whom do not understand open air preaching.
Go Stand and Speak DVD
http://www.amazon.com/dp/B004R9Z9VU/?tag=baptis04-20
People why are you against open air preaching? Open air preaching is all over the Bible and highly commended and practiced throughout history.
Here are a few concerns I have of your presentation:
1. Just because many on this board may not advocate open air preaching does not mean that they do not understand the method. Many understand why it was at one time effective, and why it has declined in effectiveness as lifestyles, culture, and technology has changed. You would do well to present your case without assuming ignorance.
2. Instead of being practiced "all over the Bible," open air preaching as you have presented on this board is, interestingly enough, absent from Scripture. Instead we find people sharing the gospel as they go their way. The Apostles seek a forum (Solomon's portico, the areopagus, the synagogues, etc). Open air preachers rarely seek an audience. I am not saying that their method is unbiblical (although it is not necessarily a biblical model). I am saying, however, that you cannot hijack passages for support. I do, however, commend you for you efforts to reach the lost.
3. You assume that open air preachers have a bad reputation. I suspect you are right, but for different reasons. I'm listing this as a fault because you merely present it as unsubstantiated fact. But the reason most think poorly of open air preachers is probably the number of wacko's out there preaching hatred rather than the gospel. The world will not understand spiritual things, and they will think the gospel foolishness, but they will readily recognize hate.
4. Who....not whom. Remember....Dr. Who, not Dr. Whom..."he vs. him." No one, I'm confident not even you growing up, used "whom" the way you do here. Just say it out loud - if it sounds stupid, then you've probably go the wrong word - if it sounds normal, then go for it. Or simply use "who."
Here are my observations and opinions:
I have yet to see an open air preacher that was remotely interested in discipling people. I have yet to see an open air preacher functioning in a manner that would present a New Testament model. I think that we must always keep in mind that members do not work in absence of the Body, and for the most part (not all, mind you, but for the most part) this has not been evident in the open air preachers I've encountered.
That said, my experience is very limited. I do not live in an area where open air preaching would be considered an effective means of discipling others. I have visited areas and events where these preachers were performing, but they were very unbiblical (the one's I've witnessed) and goofy (just adding that in as a bonus...but they were).
I have watched videos of Ray Comfort as he interacted with people on the streets...and Kirk Cameron as well. I thought that they did a good job communicating the gospel, putting themselves "out there," and genuinely engaging with people. I don't really consider this as open air preaching (just to let you know where I'm coming from).
Perhaps "open air preaching" is a lost art because it has lost its audience. At one time people would stand in the open and speak to crowds (not just preachers) because it was a legitimate forum. Perhaps changing times has altered the effectiveness of that method.