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'.

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: 13d 21h 35m
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
$49.95
Time Remaining: 15d 21h 46m
Buy It Now for only: $49.95
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: 22d 3h 34m
Buy It Now for only: $37.95
DRGW Locomotives 15mm F 1203 Model Railroad Water Slide Decal Set SJD254
DRGW Locomotives 15mm F 1203 Model Railroad Water Slide Decal Set SJD254
$32.42
Time Remaining: 24d 12h 14m
Buy It Now for only: $32.42
RGS Sunrise Locomotive 15mm F 1203 Model Railroad Water Slide Decal Set SJD255
RGS Sunrise Locomotive 15mm F 1203 Model Railroad Water Slide Decal Set SJD255
$33.54
Time Remaining: 24d 12h 17m
Buy It Now for only: $33.54

Other On30 Scale train items recently purchased through this site:

DRGW Locomotives 15mm F 1203 Model Railroad Water Slide Decal Set SJD254
O SCALE On3 On30 WISEMAN MODEL SERVICES WESTMINSTER KEROSENE LOCOMOTIVE KIT
RGS Sunrise Locomotive 15mm F 1203 Model Railroad Water Slide Decal Set SJD255
On3 On30 WISEMAN MODEL SERVICES NCNG SHORTY WHALEBACK TENDER KIT
On30 WISEMAN MODEL SERVICES 1890s GILPIN STYLE BACHMANN SHAY CONVERSION KIT