The Cast of Episode IV:

A-B
Admiral Motti:  Richard Le Parmentier
Aunt Beru:  Shelagh Frasier
Ben Kenobi:  Sir Alec Guinness
Beru Lars:  Shelagh Fraser
Biggs Darklighter:  Garrick Hagon
Brea Tonnika:  Christine Hewitt

C
C-3PO:  Anthony Daniels
Chewbacca:  Peter Mayhew
Chief Jawa*:  Jack Purvis
Commander Willard:  Eddie Byrne

D-F
Darth Vader:  David Prowse
Darth Vader's voice:  James Earl Jones
Death Star Gunner:  Grant McCune
Dr. Evazan:  Alfie Curtis
Dutch/Gold Leader:  Angus Macinnes

G
Garindan:  Sadie Eddon
General Dodonna:  Alex McCrindle
General Tagge:  Don Henderson
Gold 2/Tiree:  Jeremy Sinden
Gold 5:  Graham Ashley
Gold Leader/Dutch:  Angus Macinnes
Grand Moff Tarkin:  Peter Cushing
Greedo: Maria de Aragon

H-I
Han Solo:  Harrison Ford
Imperial Military Chief in SW:  Don Henderson
Imperial Military Chief in SW:  Leslie Schofield

J-K
John D./Red 4:  Jack Klaff
Kabe:  Barry Gnome
Kitik Keed'kak (praying mantis-like alien in the Cantina):  Jack Purvis

L-N
Leia Organa:  Carrie Fisher
Luke Skywalker:  Mark Hamill
Muftak:  Laine Liska

O-P
Obi-Wan Kenobi:  Sir Alec Guinness
Owen Lars:  Phil Brown
Ponda Baba:  Tommy Ilsley
Porkins:  William Hootkins
Princess Leia:  Carrie Fisher

Q-T
R2-D2:  Kenny Baker
Red Leader:  Drewe Hemley
Senni Tonnika:  Angela Staines
Tiree/Gold 2:  Jeremy Sinden

U-Z
Uncle Owen:  Phil Brown
Wedge Antilles:  Denis Lawson
Wuher(cantina bartender):  Ted Burnett

*this picture is not necessarily of the Chief Jawa, however it does show a Jawa. 1