There are only 4 tapes throughout the game, being, each one of them, very important to the development of the story.
Tape 1: Derelict House Footage
The first tape can be found at the 2nd floor of the Guest House on the top a desk.
Tape 2: Mia Tape
This can be picked up at the 2nd floor of the Recreation Room, right by the bar chairs.
Tape 3: Happy Birthday Tape
To gain acess to the area where the next tape is, you need the Snake Key to enter the Kid's Room. The tape is located in the Attic.
Tape 4: Old Videotape
The final tape is near where Eve makes an appearance, on the 3rd floor of the Wrecked Ship.