Gosh this could take a while!!

Sammy-
Sammus
Sammy Boy
Punk
Brat

Leroy-
Roy Boy
WeeWoy
Mama's Boy
STOP ROYMAN
LITTLE $*#@
OH NO! LEEEEEEEEROOOOOOOOOOY!

Peanut Butter-
Love Muffin
Biggun
Horsey Boy
Fur Ball

Stubby-
Stubbit
Wittle Tiny Girl
Mean Butt

Lucky-
Buddy
Coon (because he walks and looks like a raccoon from a distance)

Maggie Sue-
Nasty Girl
Ms. Tude
Monkey Face (her daddy's nick name)
Fat Girl
Mama's Sweeeeeet Baby Giiiirl (said in the grossest baby talk)

Pepper Jack-
Wile E. Coyote
Big Eyes
Silly Boy

Pete-
PetePete
Crazy Feet Pete

Pervy-
Ms. P
Baby Doll
My Precious
Sweetums


I think that covers most of the nicknames.