ROAR let me know this weekend that on-line sign ups for Nationals will close sometime Sunday evening 3-11-12. If you need to sign up after that you'll need to do it in person at the track on Thursday. This way all on-line entry fee payments will be posted to ROAR's account and it will avoid any discrepancies. Signing up Thursday will be first come first served and tech will running starting at 6, so best bet is to get it done online before Sunday.