We've searched the internet and found the largest collection of O Scale trains for sale is on eBay. Below are the listings for 'F9'.

PAIR ATLAS F9 DIESEL 601 SANTA FE IN BOX 2 RAIL
PAIR ATLAS F9 DIESEL 601 SANTA FE IN BOX 2 RAIL
$41.17 (9 Bids)
Time Remaining: 2d 5h 24m
ATLAS F9 DIESEL LOCOMOTIVES X 4 BURLINGTON NORTHERN 6102 2 RAIL
ATLAS F9 DIESEL LOCOMOTIVES X 4 BURLINGTON NORTHERN 6102 2 RAIL
$54.00 (25 Bids)
Time Remaining: 2d 5h 25m
PAIR ATLAS F9 DIESEL LOCOMOTIVES 6101 303  304 ALL NATIONAL TRUCKS 2 RAIL
PAIR ATLAS F9 DIESEL LOCOMOTIVES 6101 303 304 ALL NATIONAL TRUCKS 2 RAIL
$114.49 (12 Bids)
Time Remaining: 2d 5h 25m
3 ATLAS F9 DIESEL LOCOMOTIVES UNION PACIFIC ALL NATIONAL TRUCKS 2 RAIL BOXED
3 ATLAS F9 DIESEL LOCOMOTIVES UNION PACIFIC ALL NATIONAL TRUCKS 2 RAIL BOXED
$134.02 (9 Bids)
Time Remaining: 2d 5h 26m
5 ATLAS F9 DIESEL LOCOMOTIVES SHELLS O SCALE IN BOXES VINTAGE
5 ATLAS F9 DIESEL LOCOMOTIVES SHELLS O SCALE IN BOXES VINTAGE
$28.00 (17 Bids)
Time Remaining: 2d 5h 27m
Lionel 6983 Pennsylvania Rail Road F9 Well Car W Cable Reels 6 16983 1997 C 9
Lionel 6983 Pennsylvania Rail Road F9 Well Car W Cable Reels 6 16983 1997 C 9
$43.12
Time Remaining: 4d 30m
Buy It Now for only: $43.12
Lionel 6 16983 6983 Pennsylvania RR F9 Well Car NIB Brand New C 10 O scale
Lionel 6 16983 6983 Pennsylvania RR F9 Well Car NIB Brand New C 10 O scale
$40.00
Time Remaining: 4d 2h 5m
Buy It Now for only: $40.00
Lionel Pennsylania RR f 9 well car 6 16983 built in 1997 for boysorgirls unused
Lionel Pennsylania RR f 9 well car 6 16983 built in 1997 for boysorgirls unused
$52.21
Time Remaining: 5d 4h 34m
+ATLAS 6103 F 9 CHESAPEAKE  OHIO DIESEL LOCO MIB 2 RAIL
+ATLAS 6103 F 9 CHESAPEAKE OHIO DIESEL LOCO MIB 2 RAIL
$99.95
Time Remaining: 6d 22h 32m
Buy It Now for only: $99.95
Lionel new 6 16946 Chesaapeake  Ohio F9 well car
Lionel new 6 16946 Chesaapeake Ohio F9 well car
$40.00
Time Remaining: 7d 17h 41m
Buy It Now for only: $40.00
Lionel Pennsylvania 6983 F9 Well Car 6 16983 NIB
Lionel Pennsylvania 6983 F9 Well Car 6 16983 NIB
$39.99
Time Remaining: 15d 16h 41m
Buy It Now for only: $39.99
Lionel 6 16983 Pennsylvania 6983 RR F9 Well Car w ob
Lionel 6 16983 Pennsylvania 6983 RR F9 Well Car w ob
$44.95
Time Remaining: 18d 21h 58m
Buy It Now for only: $44.95
LIONEL 6 16946 Chesapeake  Ohio F9 Well Car NIB 14 in FREE Ship Lower 48 States
LIONEL 6 16946 Chesapeake Ohio F9 Well Car NIB 14 in FREE Ship Lower 48 States
$34.99
Time Remaining: 26d 3h 40m
Buy It Now for only: $34.99
LIONEL TRAINS 6 16983 PENNSYLVANIA RAIL ROAD F 9 WELL CAR WITH CABLE REELS
LIONEL TRAINS 6 16983 PENNSYLVANIA RAIL ROAD F 9 WELL CAR WITH CABLE REELS
$39.99
Time Remaining: 27d 55m
Buy It Now for only: $39.99

Other O Scale train items recently purchased through this site:

PAIR ATLAS F9 DIESEL 601 SANTA FE IN BOX 2 RAIL
+ATLAS 6103 F 9 CHESAPEAKE OHIO DIESEL LOCO MIB 2 RAIL
Lionel new 6 16946 Chesaapeake Ohio F9 well car
ATLAS F9 DIESEL LOCOMOTIVES X 4 BURLINGTON NORTHERN 6102 2 RAIL
Lionel Pennsylvania 6983 F9 Well Car 6 16983 NIB
PAIR ATLAS F9 DIESEL LOCOMOTIVES 6101 303 304 ALL NATIONAL TRUCKS 2 RAIL
LIONEL TRAINS 6 16983 PENNSYLVANIA RAIL ROAD F 9 WELL CAR WITH CABLE REELS
3 ATLAS F9 DIESEL LOCOMOTIVES UNION PACIFIC ALL NATIONAL TRUCKS 2 RAIL BOXED
Lionel 6 16983 6983 Pennsylvania RR F9 Well Car NIB Brand New C 10 O scale
Lionel 6983 Pennsylvania Rail Road F9 Well Car W Cable Reels 6 16983 1997 C 9
5 ATLAS F9 DIESEL LOCOMOTIVES SHELLS O SCALE IN BOXES VINTAGE
LIONEL 6 16946 Chesapeake Ohio F9 Well Car NIB 14 in FREE Ship Lower 48 States
Lionel Pennsylania RR f 9 well car 6 16983 built in 1997 for boysorgirls unused
Lionel 6 16983 Pennsylvania 6983 RR F9 Well Car w ob