“Weird Girl” character actress Michelle Meyrink.
They were the subject of a joke on Futurama once, so not totally forgotten. I looked them up after reading your post; Lorene Yarnell died a few years ago, was only 66.
In a similar vein, I’d nominate Rod Hull, an English comedian whose act was to appear with a fake emu under his arm who would then proceed to wreak havoc. Something reminded me of him a year or so ago and I watched a show about him on youtube. Sounds like he wasn’t terribly happy, being overshadowed by a puppet and all, and fell on rather lean times. Died in 1999 adjusting the TV aerial on his roof.
Sarah Holcombe is worth a mention as well. She appeared in four movies, two of them (Animal House and Caddyshack) were huge successes. Since Caddyshack, nothing.
Kristy McNichol, and “Mikey” from the Life cereal commercial.
Arsenio Hall seemed to be doing pretty well for a couple of years, and then went away seemingly abruptly.
Not when I was growing up, but while a young adult, Steve Guttenberg had quite the run, then disappeared.
Maybe I should’ve said Eddie Murphy.
I was in HS and college in the late seventies, perhaps the prime years for Entertainment Awareness, and this act sounds quirky enough to have been especially appealing to my teenage self… and yet I’m sure that I never ran into them!
Young uns let me tell ya when I was a kid:
There was a whole world of celebs that appeared on talk shows who were from a whole previous generation but which we were all familiar with.
Ethel Merman, Arthur Treacher, Jimmy Durante. Show biz used to have a recognizable evolution.
I’m not sure how that kind of knowledge gets transmitted now or if it will just end and we will all live in the eternal present.
Remember Totie Fields? She had a leg amputated and then when she died it was like she never existed.
I’m totally with you on this.
I also remember around that time that there were famous people named Kelly Monteeth, and Randy Mantooth. I had never known such names existed but I thought there must be something going on somehow.
Steve Allen, Professor Irwin Corey, Foster Brooks, Graham Kerr (the Galloping Gourmet).
Totie Fields lived on in Mrs Wallowitz.
I was shocked not long ago when **none **of the contestants on Jeopardy! (all thirty-something) could identify either Gregory Peck, Cary Grant, or Jimmy Stewart from their photographs! :eek:
My, my. How quickly we forget! :smack: 
Judge Reinhold, Fisher Stevens, Steve Guttenberg, and Phoebe Cates.
Also Meg Tilly, Jonathan Taylor Thomas, and Jami Gertz.
I remember Shields and Yarnell. How about Rodney Allen Rippy and Pink Lady and Jeff? Unlike many of the people mentioned so far (like Alan Alda, Tootie Fields and Mary Tyler Moore who still have a presence in media even today) these guys have really disappeared from the public eye.
I’d say the most famous people, to me growing up, were the people on TV shows that I used to love. WKRP In Cincinnatti, Simon and Simon, Magnum P.I.. An astonishing number of them disappeared completely - Andy Carlson, Herb Tarlek, Less Nessman, Bailey Quarters, Venus Flytrap…A.J. Simon…Rick, T.C., Higgins - never saw them again in anything that I can recall.
I get that happens with TV show stars, even today, but back then I assumed they would all be superstars.
His TV talk show was revived a couple of years ago, but only lasted one season.
He hasn’t disappeared. Not including the Shrek movies, he still makes a movie every couple of years on average. His latest movie, Mr. Church, came out just a couple of months ago.
Dean Martin. For awhile, he was the hottest thing on TV. Then the Nanny Squad moved in and “sanitized” things. :mad:
You’d think there’s something wrong with booze and broads… 
You could do worse than just take random sample of who appeared on the Hollywood Squares.
List here
Just in case you were wondering why Pink Lady and Jeff disappeared from the face of the Earth, here’s a clip of a running gag from the show.
There was also the guy who was married to Goldie Hawn and produced a few kids. He was also married to Shirly of Laverne and Shirley for quite some time. He and his brothers had two TV shows and also a pop group. Here’s there Saturday morning show. The Hudson Brothers were FAMOUS and were pulling down all the hot chicks at the time.
Tim Reid (Venus Flytrap) was in three more series after WKRP -Frank’s Place, Simon & Simon, and Sister, Sister.
WKRP was one of my favorite shows, as well.
Tim Reid (Venus) starred in several series after WKRP, including (ironically, given your post) Simon & Simon, Frank’s Place (created by Hugh Wilson, who also created WKRP), and Sister, Sister. He’s been consistently working on TV since, though in supporting roles.
Gary Sandy (Andy Travis) found it difficult to get TV roles as he aged, and transitioned to theater.
Gerald McRaney (Rick on Simon & Simon) starred in Major Dad, and he, too, has been consistently working in TV for the past 30 years.
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Edit: ninja’d by cochrane! shakes fist*