Here is a picture of the origanal casting of Phoebe, Lori Rom being the actress here. There are many rumors of why Lori left, but luckly they picked a good replacement!
TV Guide Picture
This picture is from a TV guide issue that Charmed was on the front of.
The Attic
Here you can see Prue, Phoebe, and Piper (in that respect) up in the attic, with the book of shadows.
Origanal cast
TV Guide Picture
The Attic