We tried to book the KOA in Watkins Glen in late January but everything was booked. We got placed on the waiting list.
We then booked Hickory Hill Camping Resort on Feb 01st (where the NY chapter rally was) and we got one of the last sites.
We received a call in mid July from the KOA indicating they had an opening, which we took. This was a more upscale camping facility but the price was also upscale ($101/night less 10% off as a KOA member, for full hookup pull thru). This was very convenient though (~5 minutes to track). The other site was $81.50/night less 10% as Good Sam member, for full hookup pull thru. Time to get to the track was ~40 minutes.