I got most of these facts from the watchers guide, some of them are pretty intreasting
Brian Thompson who plays Luke, also later appeared in both "Surprise" and "Innocence" as the judge.
When Buffy wakes up in bed, early in "Witch" she's wearing a T-shirt with a black cat on the front, a symbol sometimes synonymous with witchcraft.
Cemetery sequences in season one were shot at Rosedale cemetery in Los Angeles.
All the books in the stacks of the library are real books.
It takes an hour and a half to apply Angel's vamp face to David.
Angel's duster is from Hugo Boss and coats $1,000.
At the end of "The Puppet Show" when Willow runs off the stage, it was not in the script.
When Xander holds up the dummy in "The Pupper Show" and says "Redrum, Redrum", that was also not in the original script.
In "Prophecy Girl" When Angel was about to say he liked Buffy's dress, was not in the original script.(Angel:"I really like your..." Buffy:"Yeah big hit with everyone.")
David Boreanaz became a regular cast member beginning with the eppie "When She Was Bad".
Spikes car, in the original script, was intended to be a Cadillac. In reality, it's a Desoto Sportsman, California license-plate number HIA 873.
Ara Celi, who plays Ampata and Nick Brendon each wolfed down eight to ten Twinkies for one scene.
The Frat Party is the first, and thus far only, time we have seen Buffy and Cordelia drink alcohol. (Xander was the first of the group to drink alcohol, in "Teachers pet")
Sarah Michelle Geller, Alyson Hannigan, and Charisma Carpenter all wear the same shoe size.
Anthony Stewart Head visited an Amercian high school libary to prepare for his role as Rupurt Giles.
Buffy tells Kendra to watch the movie on her flight home unless it's a "Movie with a dog in it and Chevy Chase." This refrence to Funny Farm, a 1988 movie starring Chevy Chase that Geller had a small uncredited role in.
In the final fight scene between Buffy and Ted, in "Ted" both Sarah , and John Ritter were sick, Sarah had the Flu and John Had food poisning the night before.