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

KATO N gauge 209 based 500 series PS28 equipped Ch Sbu Line Basic 6 Car Set 1
KATO N gauge 209 based 500 series PS28 equipped Ch Sbu Line Basic 6 Car Set 1
$276.79
Time Remaining: 12h 46m
Buy It Now for only: $276.79
Kato N Gauge E231 System 0 Series Ch   S bu Line 6 Both Basic Set 10 1520 M
Kato N Gauge E231 System 0 Series Ch S bu Line 6 Both Basic Set 10 1520 M
$230.28
Time Remaining: 3d 20h 5m
Buy It Now for only: $230.28
Kato N Gauge E231 System 0 Series Ch   S bu Line 4 Both hematopoiesis Set 1
Kato N Gauge E231 System 0 Series Ch S bu Line 4 Both hematopoiesis Set 1
$192.44
Time Remaining: 3d 20h 7m
Buy It Now for only: $192.44
Double Track Attachment Set for Automatic Crossing Gate S Model Train
Double Track Attachment Set for Automatic Crossing Gate S Model Train
$89.19
Time Remaining: 4d 8h 42m
Buy It Now for only: $89.19
Unitrack Automatic Crossing Gate S Basic Set Model Train by Kato
Unitrack Automatic Crossing Gate S Basic Set Model Train by Kato
$221.94
Time Remaining: 4d 8h 42m
Buy It Now for only: $221.94
10 1572 Shinano Railway 115 Series Shounan Color Yokosuka Color 6Car Set S
10 1572 Shinano Railway 115 Series Shounan Color Yokosuka Color 6Car Set S
$302.90
Time Remaining: 4d 8h 42m
Buy It Now for only: $302.90
Kato HO Gauge HV 21 HO Uni Track Automatic Traffic Signal S Set 3 131 Japan
Kato HO Gauge HV 21 HO Uni Track Automatic Traffic Signal S Set 3 131 Japan
$193.93
Time Remaining: 4d 8h 42m
Buy It Now for only: $193.93
KATO N gauge 251 based super view Dancer appeared during coating 10 Car Set S
KATO N gauge 251 based super view Dancer appeared during coating 10 Car Set S
$308.10
Time Remaining: 6d 10h 46m
Buy It Now for only: $308.10
KATO N gauge 251 based super view Dancer appeared during coating 10 Car Set S
KATO N gauge 251 based super view Dancer appeared during coating 10 Car Set S
$269.39
Time Remaining: 11d 23h 10m
Buy It Now for only: $269.39
1950S ARROW SAGO BATTERY OPERATED TRAIN SET SANTA FE CHIEF  AA46
1950S ARROW SAGO BATTERY OPERATED TRAIN SET SANTA FE CHIEF AA46
$39.95
Time Remaining: 14d 23h 5m
Buy It Now for only: $39.95

Other On30 Scale train items recently purchased through this site:

1950S ARROW SAGO BATTERY OPERATED TRAIN SET SANTA FE CHIEF AA46
KATO N gauge 251 based super view Dancer appeared during coating 10 Car Set S
KATO N gauge 251 based super view Dancer appeared during coating 10 Car Set S
Kato N Gauge E231 System 0 Series Ch S bu Line 4 Both hematopoiesis Set 1
Kato N Gauge E231 System 0 Series Ch S bu Line 6 Both Basic Set 10 1520 M
KATO N gauge 209 based 500 series PS28 equipped Ch Sbu Line Basic 6 Car Set 1
Kato HO Gauge HV 21 HO Uni Track Automatic Traffic Signal S Set 3 131 Japan
Unitrack Automatic Crossing Gate S Basic Set Model Train by Kato
Double Track Attachment Set for Automatic Crossing Gate S Model Train
10 1572 Shinano Railway 115 Series Shounan Color Yokosuka Color 6Car Set S