GL libraries...for commandline compiling


I had a general newbie kinda question to ask;

okay if I am gonna be compiling some GL stuff from the command line where should I place my libraries?
Would I throw them into usr/local/lib/? or maybe usr/lib/ ? I know where they are for PB but when I compile from commandline of course they are quite invisble to the compiler.. where does the compiler look irst I geuss is my question and how can I change this.? .in the .cshrc?