Allyn, there is going to be a knap in in Fairview Heights IL on June 3 - June 6th this year. Its called the Devil's Hole Knap in. You can find all the information on the schedule of events on flintknappers dot com. That would be the closest one to O'Fallon that I know of this year. Larry Kinsella puts on this knap in and he is very knowledgeable about the different types of chert in the St. Louis area. You may want to try so go over there for a day.
Typically there is a knap-in every year in May near east of Boonville MO on I 70 but it may not be happening this year. I cannot find any information about it.
Hopefully MOJam gets to happen this year. It will be great to see everybody again, and meet all the new people.
Neal