We've searched the internet and found the largest collection of On30 Scale trains for sale is on eBay. Below are the listings for 'scale model trains'.

RS O On3 On30 SEQUOIA SCALE MODELS BRANCHLINE SAND HOUSE AND BUCKET CRANE KIT
RS O On3 On30 SEQUOIA SCALE MODELS BRANCHLINE SAND HOUSE AND BUCKET CRANE KIT
$32.00 (3 Bids)
Time Remaining: 7h 43m
Suncoast Models 004 148 O Scale Logging Camp Craftsman Kit On3On30
Suncoast Models 004 148 O Scale Logging Camp Craftsman Kit On3On30
$56.00 (8 Bids)
Time Remaining: 8h 3m
CHB Models VB 630 148 O Scale Vertical Boiler Kit On3On30 LoggingMachinery
CHB Models VB 630 148 O Scale Vertical Boiler Kit On3On30 LoggingMachinery
$54.95
Time Remaining: 8h 3m
KMP Models O Scale Steam Powered Sawmill w Planer LumberLogging Interior MIB
KMP Models O Scale Steam Powered Sawmill w Planer LumberLogging Interior MIB
$129.95
Time Remaining: 8h 13m
RS O On3 On30 COLORADO SCALE MODELS 475 LEAVERITE MINE CRAFTSMAN KIT
RS O On3 On30 COLORADO SCALE MODELS 475 LEAVERITE MINE CRAFTSMAN KIT
$93.47 (5 Bids)
Time Remaining: 9h 29m
Morgan Hill Models MHM On30 O Scale Stone Water Tank w Shed Kit
Morgan Hill Models MHM On30 O Scale Stone Water Tank w Shed Kit
$84.95
Time Remaining: 4d 8h 3m
KMP Models O On30 Scale Craftsman Logging Kit Spar Tree Model Trains New
KMP Models O On30 Scale Craftsman Logging Kit Spar Tree Model Trains New
$56.95
Time Remaining: 4d 20h 8m
Buy It Now for only: $56.95
KMP Models O On30 Scale Craftsman Logging Kit Steam Sawmill with Planer New
KMP Models O On30 Scale Craftsman Logging Kit Steam Sawmill with Planer New
$179.00
Time Remaining: 4d 20h 8m
Buy It Now for only: $179.00
West side  Pacific Traction Pacific Fast Mail Balboa Scale Models Fomras
West side Pacific Traction Pacific Fast Mail Balboa Scale Models Fomras
$500.00
Time Remaining: 5d 4h 35m
Buy It Now for only: $700.00
Western Scale Models M16 Blacksmith Shop SEALED Kit O On3 0n30 1 4 Scale
Western Scale Models M16 Blacksmith Shop SEALED Kit O On3 0n30 1 4 Scale
$26.00 (3 Bids)
Time Remaining: 5d 10h 12m
Western Scale Models M 51 The Rowe Inclined Shaft Headframe  Hoist House Kit
Western Scale Models M 51 The Rowe Inclined Shaft Headframe Hoist House Kit
$58.49 (10 Bids)
Time Remaining: 5d 10h 24m

Other On30 Scale train items recently purchased through this site:

Western Scale Models M 51 The Rowe Inclined Shaft Headframe Hoist House Kit
KMP Models O On30 Scale Craftsman Logging Kit Steam Sawmill with Planer New
Western Scale Models M16 Blacksmith Shop SEALED Kit O On3 0n30 1 4 Scale
Suncoast Models 004 148 O Scale Logging Camp Craftsman Kit On3On30
RS O On3 On30 COLORADO SCALE MODELS 475 LEAVERITE MINE CRAFTSMAN KIT
Morgan Hill Models MHM On30 O Scale Stone Water Tank w Shed Kit
KMP Models O Scale Steam Powered Sawmill w Planer LumberLogging Interior MIB
CHB Models VB 630 148 O Scale Vertical Boiler Kit On3On30 LoggingMachinery
RS O On3 On30 SEQUOIA SCALE MODELS BRANCHLINE SAND HOUSE AND BUCKET CRANE KIT
West side Pacific Traction Pacific Fast Mail Balboa Scale Models Fomras
KMP Models O On30 Scale Craftsman Logging Kit Spar Tree Model Trains New