yep, ive driven watkins glen before and i will tell you flat out its a fucking intimidating course
its really big and it can get a little confusing remembering what is coming up next
there also isnt much run off area if you fuck up a corner... some of the barricades were right at the edge of the track... it was my second time on a track when i went to the glen... it was fun... but i would have gotten a lot more out of it if i had a little more experience
limerock is an excelent course, its small enough that it is easy to remember what is next, but it is actually a VERY challenging course, and its not easy to get it completely nailed down
NHIS is a perfect course for smaller cars that rely on handling... many equate it to a really large autox course... i havent been there yet but i am looking forward to hitting it this year
as far as where to start i highly recommend hitting several autox events (at least half a season) before you go to the track
autox teaches you the limits of the car at a much lower speed and with much less risk involved if you do fuck up or pass the limits (cones are better to hit than a wall, a barricade, or even worse, another car)
autox also teaches you that the trick to being fast is being smooth (jerking the car around on a road course in an 80mph corner and its not going to be pretty)
autox will teach you some basics of proper line choice (its much harder to judge on an autox course, if you can do it there then you should be able to handle it on a road course)
autox experience will make you a better road courser (while road course experience can spoil you, and actually hurt your performance on an autox course)
also if you can go to the track already understanding and being proficient at trail braking and heal-toe shifting, it will help you a great deal
the SCDA instructors are great... the classroom time was also quite helpful... i learned more on my first 8 hour day at the track than i did in the previous 8 years id had my license