Yikes. No replies and this has been up a week? I'll shoot!
I know the IPMS Nationals convention is happening in Omaha next summer. Lincoln's a pretty big city, though. Have you tried googling 'model clubs lincoln' or somesuch? Worth a shot. Before FSM updated their website, they had a listing for clubs by state, too, I thought. I haven't been able to find it.
Maybe with the bump of my reply here others will chime in. Sorry for the delayed reply!
-Chris