There is no listing on the web right now for collectors of Robert Blair Martin's Springbok puzzles. This guide fixes this oversight! If I'm in need of something to do one day, I'll add some pictures of each of the puzzles.

400 piece puzzles:
“The North Pole Toy Company 2000” (Springbok #?, 400 pieces, 2000)

500 piece puzzles:
“Pops-town” (Springbok plz4094, 500 pieces, 1978)
“All-Star Calliope Band” (Springbok plz4124, 500 pieces, 1981)
“Mom’s Day Off” (Springbok plz4138, 500 pieces, 1982)
“The Last Resort” (Springbok/Ambassador plz206j, 500 pieces, 1983)
“And the Winner is...” (Springbok plz3203, 500 pieces, 1985)
“What was the name of that TV show?” (Springbok plz3419, 500 pieces, 1985)
“Super Dome Sunday” (Springbok plz4185, 500 pieces, 1985)***disputed authorship***
“A Short round of Golf” or "Putt-Putt Puzzle" (Springbok pzl2205; 500 pieces, 1985)
“The Ant Ranch” (Springbok plz3701, 500 pieces, 2000)

700 piece puzzles:
Verticalville” (Springbok/Ambassador plz4085, 700 pieces, 1977)
“Oh, Christmas Tree” (Springbok plz9809,  700 pieces, 1988)
“Verticalville II” (Springbok plz9804, 700 pieces, 1986) 

1000 piece puzzles:
“Mountainside Park” (Springbok pzl5914, 1000 pieces, 1979)
“The Sovereign State of Euphoria” (Springbok pz5934, 1000 pieces, 1983)
“Computers: the Inside Story” (Springbok pzl5936/pzl6101, 1000 pieces, 1983/1984)
“The Global Games” (Springbok pzl5956, 1000 pieces, 1984)

“The Good, Old U.S. of A.” (Springbok pzl5925, 1000 pieces)
“California, a State of Mind” (Springbok pzl5945, 1000 pieces)
“Texas, a State of Mind” (Springbok pzl5946, 1000 pieces)
“Florida, a State of Mind” (Springbok pzl5947, 1000 pieces)

1500 piece puzzles:
“Space Station” (Springbok plz?, 1500 pieces)
“Welcome to Fracture Falls” (Springbok plz5973, 1500 pieces)

If you know of others that I could add to the list, please tell me!