First starring film:

THE BIG TRAIL (Fox, 1930)

In Buck Jones & Tim McCoy oaters at Columbia Pictures:

RANGE FEUD (Columbia, 1931) Buck Jones
TEXAS CYCLONE (Columbia, 1932) Tim McCoy
TWO-FISTED LAW (Columbia, 1932) Tim McCoy

In 3 non-western cliffhangers for Nat Levine and Mascot:

THE SHADOW OF THE EAGLE (Mascot, 1932)
THE HURRICANE EXPRESS (Mascot, 1932)
THE THREE MUSKETEERS (Mascot, 1933)

At Warners for his first western Series:

RIDE HIM COWBOY (Warners, 1932)
THE BIG STAMPEDE (Warners, 1932)
HAUNTED GOLD (Warners, 1932)
THE TELEGRAPH TRAIL (Warners, 1933)
SOMEWHERE IN SONORA (Warners, 1933)
THE MAN FROM MONTEREY (Warners, 1933)

With producer Paul Malvern's Lone Star Productions (released by Monogram):

RIDERS OF DESTINY (Lone Star/Monogram, 1933)
SAGEBRUSH TRAIL (Lone Star/Monogram, 1933)
THE LUCKY TEXAN (Lone Star/Monogram, 1933)
WEST OF THE DIVIDE (Lone Star/Monogram, 1934)
BLUE STEEL (Lone Star/Monogram, 1934)
THE MAN FROM UTAH (Lone Star/Monogram, 1934)
RANDY RIDES ALONE (Lone Star/Monogram, 1934)
THE STAR PACKER (Lone Star/Monogram, 1934)
THE TRAIL BEYOND (Lone Star/Monogram, 1934)
THE LAWLESS FRONTIER (Lone Star/Monogram, 1934)
'NEATH ARIZONA SKIES (Lone Star/Monogram, 1934)
TEXAS TERROR (Lone Star/Monogram, 1935)
RAINBOW VALLEY (Lone Star/Monogram, 1935)
THE DESERT TRAIL (Lone Star/Monogram, 1935)
THE DAWN RIDER (Lone Star/Monogram, 1935)
PARADISE CANYON (Lone Star/Monogram, 1935)

More westerns for the New Republic Pictures company (all produced/supervised by Paul Malvern):

WESTWARD HO (Republic, 1935)
THE NEW FRONTIER (Republic, 1935)
THE LAWLESS RANGE (Republic, 1935)
THE OREGON TRAIL (Republic, 1936)
THE LAWLESS NINETIES (Republic, 1936)
KING OF THE PECOS (Republic, 1936)
THE LONELY TRAIL (Republic, 1936)
WINDS OF THE WASTELAND (Republic, 1936)

At Universal for some non-westerns:

THE SEA SPOILERS (Universal, 1936)
CONFLICT (Universal, 1936)
CALIFORNIA STRAIGHT AHEAD (Universal, 1937)
I COVER THE WAR (Universal, 1937)
IDOL OF THE CROWDS (Universal, 1937)
ADVENTURE'S END (Universal, 1937)

At Paramount for a solo film with Johnny Mack Brown:

BORN TO THE WEST (Paramount, 1937) (alternate title: HELL TOWN)

As "Stony Brooke" of the Three Mesquiteers (with Ray Corrigan & Max Terhune):

PALS OF THE SADDLE (Republic, 1938)
OVERLAND STAGE RAIDERS (Republic, 1938)
SANTA FE STAMPEDE (Republic, 1938)
RED RIVER RANGE (Republic, 1938)
THE NIGHT RIDERS (Republic, 1939)
THREE TEXAS STEERS (Republic, 1939)

And more Mesquiteers (with Ray Corrigan & Raymond Hatton):

WYOMING OUTLAW (Republic, 1939)
NEW FRONTIER (Republic, 1939)
(NEW FRONTIER was retitled FRONTIER HORIZON for TV release to avoid confusion with Wayne's earlier film, THE NEW FRONTIER (Republic, 1935))

For Director John Ford:

STAGECOACH (Walter Wanger/United Artists, 1939)


Note: the above filmography represents Wayne starring films and western film supporting roles, and does NOT include roles and bit parts in some 1920s silents and early 1930s non-westerns.  However, I did include the McCoy and Jones oaters at Columbia for reference purposes.