During one scene, after Shari has left, Ed is in his video store and sees a woman in a wig and sunglasses outside whom he recognizes as Shari in disguise. In the background you can see a poster for the movie Vertigo (1958), which features a woman disguising herself in a similar fashion.
There are two tributes to Don Knotts in the film. The Ghost and Mr. Chicken and The Incredible Mr. Limpett are shown on the video store counter. An advertisement for "Fife" is shown on the screen. Don Knotts played Barney Fife on the Andy Griffith show, also starring Ron Howard.
When Ed is invited to drive the zamboni at the Sharks game. He is talking about the San Jose Sharks. The Sharks first arrived in the Bay Area in 1991 and played their first 3 years in Daily city, a town just outside San Francisco (where the movie takes place) since 1993 they play their home games 45 min south in San Jose, locally known as the Shark Tank.
This film and "The Truman Show" were aware the other project existed during their pre-production phases, but Edtv was not that concerned for two reasons: they knew that TTS was very much a drama and their film would be a comedy, and they did not expect the other film to be a huge hit because they felt audiences would not turn out in large numbers to see Jim Carrey doing a drama that was so removed from his multi-year run of comedic blockbusters. One side effect that hurt Edtv was the huge summer 1998 success of "The Truman Show", which led Universal to insist that the promotions for Edtv make it look like more of a broad slapstick comedy than it actually was, and contributed to the film underachieving after its March 1999 release.