There were just a few VHS releases over the years which suggests production costs were high and expectations for sales were low.. Your best bet to track these down is to search the online auction sites. If you have any details or cover scans for ones I'm missing please add a comment.

From a fellow collector:

Title
African Journey (1990)
All Heart (1997)
An Evening with Sir Howard Morrison (1990)
Back of the Y Masterpiece Television (2001-2)
Before the Mast (2000)
Billy T James Show (1981-88)
Blood, Sweat and Touring (1990)
Boy from Andromeda, the (1991)
Bumble (?)
Captain's Log (2001-2)
Dress Up Box, the (2001-2005ish)
Epitaph (2001)
Fire-Raiser, the (1986)
Good, the Bad and the Rugby (1989)
Grasscutter, the (1988)
Hairy Maclary (1996)
Haunting of Barney Palmer, The (1987)
Heart of the High Country (1986)
Heartland (1992 - 96)
Hercules: The Legendary Journeys (1995 - 99)
Ihaka: Blunt Instrument (2000)
Lawless (1999-2001)
Letter to Blanchy (1996)
Magical World of Margaret Mahy, the (1994)
Mark II Zephyr (Mark II)
Moko Toa (1998, 2000)
Mortimer's Patch (1980-84)
Mud and Glory (1990?)
Nearly No Christmas (1982)
No Latitude for Error (1994)
Nutcase (1980)
Oscar and Friends (1996)
Party Animals, The (2003 - 2004)
Popstars (1999)
Rainbow Warrior Conspiracy, The (1988)
Ray Bradbury Theatre, The (1991-97)
Rogue Stallion, the (1990)
Rugged Gold (1994)
Sam McGredy's World of Roses (1998)
Savage Play (1994)
Shipwreck (2000)
Shortland Street (1992-Now)
Sinking of the Rainbow Warrior, the (1993)
Skycrane (1983-84)
Son of a Gunn Show (1992-95)
Sound and the Silence, the (1993)
Steel Riders (1987)
Suzy's World (1999-2003)
Town and Around (1965-70)
Typhon's People (1993)
Wild South (1981-97)
Worzel Gummidge Down Under (1986-87)
Xena: Warrior Princess (1995-2002)
Young Hercules (1998-99)