Forget the license, You would need to attend a 3 day school such as Justin Bell's or Skip Barber ($3000+) to get it.
You can apply to NASA either at
http://www.nasaproracing.com/
or through the Florida Chapter
You will be given an instructor there (for those who don't have a license). You will also need a SNELL 95 or newer Helmet and you need to wear long sleeves, long pants, and closed shoes.
All the info should be at the website I posted.
I'll know after XMAS if i'll be going (it's on my list

)
Apply quick the instructors are few...