Sara Sidle !
I'm pretty sure she left somewhere in season 7.
For Warrick..
First of all, He attacked a paparazzi member.
[
"CSI" Star Beats the Living Crap Out of TMZ Photog - TMZ.com]
And recently he was busted for Coke, Ecstasy AND Heroine.
[
"CSI" star Gary Dourdan faces drug charges - Yahoo! News]
I'm sure that probably has something to do with him being fired.