If racing, then you will need a license and see which class you want to run in. Check SCCA, BMW CCA, NASA or TCRA. You have to go through a program before getting the race license. They have specific race days. Just visit the various websites and they have a race schedule for next year.
Otherwise, I am not aware of an event where you can race in your daily driver at Big Willow or any track.
Technik Engineering ASA Stage 1.
Supercharged E46 M54B25.
2011 NASA TTC So Cal Champion!
Technik Engineering oil cap o-ring maintenance kit available.