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

On3 On30 WISEMAN MODEL SERVICES SHORTY TENDER FOR FORNEY AND OTHERS KIT
On3 On30 WISEMAN MODEL SERVICES SHORTY TENDER FOR FORNEY AND OTHERS KIT
$39.95
Time Remaining: 11d 12h 40m
Buy It Now for only: $39.95
O SCALE On3 On30 WISEMAN MODEL SERVICES WESTMINSTER KEROSENE LOCOMOTIVE KIT
O SCALE On3 On30 WISEMAN MODEL SERVICES WESTMINSTER KEROSENE LOCOMOTIVE KIT
$37.95
Time Remaining: 13d 10h 36m
Buy It Now for only: $37.95
On30 WISEMAN MODEL SERVICES 1890s GILPIN STYLE BACHMANN SHAY CONVERSION KIT
On30 WISEMAN MODEL SERVICES 1890s GILPIN STYLE BACHMANN SHAY CONVERSION KIT
$119.95
Time Remaining: 15d 19h 58m
Buy It Now for only: $119.95
On3 On30 WISEMAN MODEL SERVICES NCNG SHORTY WHALEBACK TENDER KIT
On3 On30 WISEMAN MODEL SERVICES NCNG SHORTY WHALEBACK TENDER KIT
$59.95
Time Remaining: 17d 22h 21m
Buy It Now for only: $59.95

Other On30 Scale train items recently purchased through this site:

O SCALE On3 On30 WISEMAN MODEL SERVICES WESTMINSTER KEROSENE LOCOMOTIVE KIT
On30 WISEMAN MODEL SERVICES 1890s GILPIN STYLE BACHMANN SHAY CONVERSION KIT
On3 On30 WISEMAN MODEL SERVICES SHORTY TENDER FOR FORNEY AND OTHERS KIT
On3 On30 WISEMAN MODEL SERVICES NCNG SHORTY WHALEBACK TENDER KIT