From the Midwest sports car club. Here's the link to the club:
http://www.midwestscc.com/viewtopic.php?t=472&page=1

From their site:

Thunder Event - Exotics/Sports Cars Well for the last 2 years we've held our season opener event to coorespond w/ http://www.thunderoverlouisville.org/. It is that time of year again so you Indiana boys need to make plans to come down. Event will be 10:00am in Louisville on Saturday April 12th. A get together and cruise followed by lunch and another early afternoon run. For those that want to stick around there is an air show and huge fireworks show that night.

So who is in so I can start a head count and get details together.