http://www.behindthename.com/ - To check source of first name

Nicknames / Given Names
Bell, Bella, Belle / Arabelle, Anabelle, Belinda, Elizabeth, Isabel, Isabella, Mirabel, Rosabel
Belle / Mabel, Sybil
Bess, Bessie, Bessy, Beth, Bette, Bettie, Bettie, Betsy, Betsey, Bitsy / Elizabeth, Elisabeth
Bob, Bobby / Robert
Bobbi, Bobbie / Roberta
Boots / Bertha
Bridey, Brie / Bridget
Carrie, Carry / Caroline, Charlotte
Cindy / Cynthia, Cinthia, Lucinda
Daisy / Margaret
Delia / Adelia, Adele, Cordelia
Dick / Richard
Dobbin / Robert
Dode, Dody / Dorothy, Theodore
Dora / Dorothy, Eudora, Theodora
Ed, Eddie, Eddy / Edgar, Edmund, Edward, Edwin, Edwina
Effie, Effy / Euphemia, Evelyn
Eliza / Elizabeth, Elisabeth
Greta / Margaret, Margaretha
Ella, Ellie / Eleanor, Elenora
Fannie, Fanny / Frances
Frankie / Frances (female), Francis (male), Franklin
Genie / Eugenia
Ginger, Ginny / Virginia
Hal / Harold, Henry
Hank, Harry / Henry
Hattie / Harriet, Harriett
Hettie / Esther, Henrietta, Hester
Jack / John
Jamie / James, Jameson
Jenny / Jane, Janet, Jeanette, Jennett, Virginia
Jim, Jimmy / James
Jock, Johnnie, Johnny / John
Kate, Katie, Katy, Kay, Kit, Kitty / Katherine
Lena / Angelina, Helena, Magdalena, Paulina, Selena, etc.
Lisa, Lise, Liz, Lizzie / Elizabeth, Elisabeth
Lucy / Lucinda
Madge, Maggie, Midge / Margaret
Mamie / Mary
Marty, Martie, Mattie / Martha
May / Mary
Meg, Megan / Margaret
Millie, Milly / Amelia, Mildred
Moll, Mollie, Molly / Mary
Nell, Nellie, Nelly / Eleanor, Elenora, Ellen, Helen
Nora / Elenore, Elenora, Honora, Honoria
Ollie / Olive, Olivia, Oliver
Pat, Patsy, Patty, Pattie / Martha, Matilda, Patricia, Patience
Peg, Peggy / Margaret
Penny / Penelope
Polly, Pollie / Mary, Paula
Rich, Richy, Rick / Richard
Rob, Robbie, Robby / Robert
Robin / Robert, Roberta
Sadie, Sally, Sallie / Sarah
Sam, Sammy, Sammie / Samuel, Samson, Samantha
Sukie, Suchie, Suchy / Susan, Susanna, Susannah
Tad / Theodore
Ted, Teddy / Edward, Theodore
Theo / Theodore
Tilly / Temperance
Tillie / Matilda, Mathilda
Tina / Christina
Trina / Catherine, Katherine
Winnie / Winefred, Winifred