It would vary but I would expect that besides HEMMINGS and OLD CARS WEEKLY, local and regional newspapers, local radio & TV stations and any popular old car publications distributed in the area of the meet with an upcoming events listing should be included. Between the local sources and the old car magazines, you're trying to build up possibility of exposure.
For the "working press" you may want to have someone available with a nicely restored (original rather than modified) car available to let properly accredited people sit behind the wheel to get a feel for what the car is like and even go with him or her for a short drive (plan the course in advance). If things go right, the camera person would go along and what they record may be part of the story they do. Remember, odds are that whoever comes to cover the event will probably be younger than the cars themselves and don't know anything about them. This offer would not be extended to the public at large.