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 railways'.

SUPERB BRIEFCASE MODEL RAILWAY LAYOUT AND TRAIN BY MOUNTAIN LAKE MODELS RAILWAYS
SUPERB BRIEFCASE MODEL RAILWAY LAYOUT AND TRAIN BY MOUNTAIN LAKE MODELS RAILWAYS
$1,621.61
Time Remaining: 8d 20h 59m
Buy It Now for only: $1,621.61
Dundas Models DM25 Festiniog Railway 2 Ton Steel Sided Slate Wagon 5 Pack T48
Dundas Models DM25 Festiniog Railway 2 Ton Steel Sided Slate Wagon 5 Pack T48
$35.56
Time Remaining: 12d 8h 15m
Buy It Now for only: $35.56

Other On30 Scale train items recently purchased through this site:

SUPERB BRIEFCASE MODEL RAILWAY LAYOUT AND TRAIN BY MOUNTAIN LAKE MODELS RAILWAYS
Dundas Models DM25 Festiniog Railway 2 Ton Steel Sided Slate Wagon 5 Pack T48