This whole idea is pretty hilarious (and awesome). Schedule a time traveler convention, publicize it well, and hope people from the future show up.
Can’t the time travelers just hear about it from the attendees, and travel back in time to attend?
Yes, they can! In fact, we think this will happen, and the small number of adventurous time travelers who do attend will go back to their “home times” and tell all their friends to come, causing the convention to become a Woodstock-like event that defines humanity forever.
Unfortunately, we of the present (2005) don’t have time travel, and so we only have one chance at observing the convention. If the time travelers don’t leave us their secrets, we won’t be able to go back in time and see our convention in all its glory unless it is publicized in advance.