A Wizard and His Familiar

[Babuguuscooties]

I was wondering if there were any sources on the various wizard familiars? I know they are mostly just fluff for RP, and that's just fine. What I'm after is some source of information that details maybe why a wizard would likely choose a weasel, or a chicken as his familiar. Are there familiars more common among certain specialist wizards, or wizards of certain regions etc.


Thanks guys!