Here is a list of all of the cast members (yes, all of the cast, not just the newsies).
The Newsies
Jack Kelly.....................Christian Bale
David Jacobs................David Moscow
Spot Conlon..................Gabriel Damon
Racetrack Higgins.............Max Casella
Kid Blink.........................Trey Parker
Mush..............................Aaron Lohr
Crutchy......................Marty Belafsky
Boots........................Arvie Lowe, Jr.
Dutchy......................Ivan Dudynsky
Bumlets.....................Dominic Lucero
Snitch..........................Dee Caspary
Jake......................Joseph Conrad II
Itey.......................Dominic Moldano
Specs............................Mark David
Skittery...............Michael A. Goorjian
Snoddy.....................Robert Feeney
Pie Eater......................David Sidoni
Swifty...........................Kevin Stea
Snipeshooter............Matthew Fields
The Rest of the Cast
Bryan Denton.........................Bill Pullman
Medda Larkson.....................Ann-Margret
Joseph Pulitzer....................Robert Duvall
Sarah Jacobs...........................Ele Keats
Mayer Jacobs..................Jeffrey DeMunn
Esther Jacobs..........Deborra-Lee Furness
Kloppman.....................Mark Lawrence I
Ten-Pin..........................Kevin Michaels
Nun #1.............................Sylvia Short
Nun #2....................Melody Santangelo
Nun #3...............................Lois Young
Teddy Roosevelt...David James Alexander
Toby........................Gregg Kent-Smith
Weasel..........................Michael Lerner
Oscar Delancey............Shon Greenblatt
Morris Delancey............David Sheinkopf
Warden Snyder..................Kevin Tighe
Seitz.............................Charles Cioffi
Jonathan....................Mark Lowenthal
Judge Monoham.............William Boyett
Patrick's Mother..............Jo Ann Harris
Chief of Police Devery...Frank Girardeau
Captain McSwain...............Shay Duffin
Bailiff...............................Terry Kohl
Bunsen.......................Tom Finnegan
Gammon.........................I.M. Hobson
Policeman...................Frank Novak II