Does anybody remember an episode where Bob Barker once
mentioned the newsgroup alt.tv.game-shows?

i don't remember that episode but i vividly recall one in whic Bob Eubanks dropped by! Barker was asking for the next item up for bid and out pushed a sofa and in that sofa sat Eubanks! the stunt happened because CBS had just announced that "Card Sharks" was going to be returning and that Eubanks would be the new host. CBS was billing the line-up as the "Three Bobs". you'll have Bob Goen at 10am with "Black Out", Bob Eubanks at 10:30 with "Card Sharks", and Bob Barker at 11am with "The Price is Right".

I believe I remember him mentioning "some gameshow website" on air (referring obviously to ATGS), but never said it outright.