I've been on one of their rally events in northern California and it blew my mind. 3 days in a 1978 Rabbit and 1000 miles. Everyone was so friendly. Imagine a car show while your going though the canyons at speed. You can feel the engines roar.
The site has info on what they do and when the events are.
MrCarGeek Pros for Targa Rally
Easy to navigate
MrCarGeek Cons for Targa Rally
Not too much to the website.