You can go home again - and your rerun family will always be there waiting. Andy and Barney and Gilligan and Mr. Ed stepped into our living rooms decades ago, and they've never left.

That's obvious to anyone with a cable hookup. What's less well-known is just how many clubs, organizations and societies exist for the preservation and general well-being of television characters of yore.With such a commanding record in the courtroom, you would think Perry Mason could pretty well take care of himself. Nevertheless, the National Association for the Advancement of Perry Mason is there just in case.

Mayberry must be about the most lovable town in the history of civilization, but just to make sure it gets its due, there's the Andy Griffith Show Appreciation Society. The Kramdens and the Nortons have all but been knighted by the Royal Association for the Longevity and Preservation of the Honeymooners (RALPH, for short).

Gilligan and the Skipper did manage to get themselves shipwrecked on a three-hour cruise, so maybe they do need their fan club to watch out for them. And for those earthlings who took one of the all-time wrong turns, there's the Lost In Space Fannish Alliance.

The Bionic Woman has her own fan club. So does Mister Ed - along with a Museum of Ed. "Star Trek" of course has several clubs and a zillion or so devotees, and "Dark Shadows" also boasts multiclub status. Enduring fan clubs even have been inspired by Keith Partridge, Napoleon Solo and even Sue Ann Nivens (the cooking-show hostess on "The Mary Tyler Moore Show").

The list goes on, but it's hard to get a precise count.

"I have a file of between 1,200 and 1,500 fan clubs, and I haven't got all of them, because they are often hard to find. I wouldn't be surprised if there are more than 2,500 of them out there," says Blanche Trinajstick, president of the National Association of Fan Clubs in Pueblo, Colo.

Those figures do include other clubs, such as those for musicians. But Mrs. Trinajstick says organizations devoted to old television shows are among the most devoted.

" `Gilligan's Island,' `Mr. Ed,' a lot of those old television shows have fan clubs. `The Andy Griffith Show' has a very large following. I really don't know what it is. There was something about those shows people could relate to," she says.

"I think it is a way of staying in touch with the show. There was just something fascinating about many of those old shows that is really strong."

Flint Mitchell, president of the 1,500-member Lost in Space Fannish Alliance in St. Louis, agrees.

"Basically, the shows that were on in the '60s were more creative, or at least people think they were," he says.

"The show takes them back to the time of their childhood when things seemed simpler. They probably watch it as a way to forget their problems."

They're hardly a bunch of passive, couch-potato nostalgia junkies, however. Devotees of old TV shows are quick to take action when their shows are threatened.

John Meroney of Clemmons, N.C., founded the Andy Griffith Show Appreciation Society in 1983 to persuade a television station in his area not to drop reruns of the show. The idea caught on rapidly as fans began to lobby stations nationwide to return Mayberry to the air. Today the organization has more than 7,000 members, and Andy is practically everywhere.

"At this point, the show is fairly accessible, if not on local stations, certainly on cable. People don't have the problem finding it that they did in the early '80s. Obviously the pressure that people put on stations does work," Meroney says.

The organization continues its lobbying efforts, acts as a consultant for projects like last year's Turner Broadcasting special, "Thirty Years of Andy Griffith," and publishes "The Mayberry Gazette." The last is published six times a year, and takes its name and format from the town newspaper on the show.

"One of our most popular features is called `Mayberry after Midnight.' It was a gossip column mentioned in some of the episodes. A lot of it is presented as if you were actually reading The Mayberry Gazette," Meroney says.

Also included is a column with the same title of the sports column Barney Fife used to brag about writing for his high school paper, "Pickups and Splashes from Floor and Pool."

"We did a demographic study of our subscribers and found the average age was 35-40. That puts them about the same age as Ron Howard (who played Andy's son, Opie). So they were actually growing up while the show was on, and it was a part of their young life," Meroney says.

"A lot of them live in large urban areas, and many write us and say they grew up watching the show and now it is like going back in time for them and reliving the pleasant experience.

"Of course there could never be a town really like Mayberry. It was a utopian world. But we still all like to think there is a place like that."