Well, my approach was to hire a small group of people to help out at a trade show, give them a some training and watch how they worked during the show. At the end of the process I offered one of them a permanent job. It worked out very well.

I did this through an ad in Craigs List. I effectively asked for people comfortable with technology, able to learn quickly and with great people skills that could be applied in the context of sales presentations in a trade show environment. I did get quite a variation of responses. I selected a small group I thought would do well.