Links

Joe Warren's N Scale Layouts blog
Brendan's "D&H 2nd 4th sub Champlain Division" blog
Greg's "L&N RR Knoxville Division"
Rod's "Santa Fe Southern Division" blog
Rob's "Pacifico" layout
Darren's "Cann River" VR layout on YouTube
Geoff's "Zebras and Warbonnets" (HO) blog
Bill's Sn3 "Vance Junction" layout
Shelton's "VR Western Victoria" (HO) site
Doug Cook's "ATSF Shortland Sub" layout photos.
Gordon Bliss's N scale "Santa Fe - All the Way" layout (YouTube)
Reefers on Gordon Bliss's "Santa Fe - All the Way" layout (YouTube)
"El Capitan" on Gordon Bliss's layout
Brad Myers' very informative "N scale DCC" site
John Parker's "Barren Creek & Santa Fe" (HO) layout tour
Lance Mindheim's blog
Rick Spano's "Sceniced and Undecided Railway"

Rob Spangler's "WP 8th sub" blog

The Model Railway Show
My YouTube page 
Ted Culotta's "Prototopics" blogspot

More GC&SF layouts

Links to photos and videos I've found of other layouts based on the GC&SF. From what I can find, the layout owners don't have a specific blog/site dedicated to their layouts.

James Peterson's HO "Gulf, Colorado & Santa Fe" (YouTube video)
Paul Dauzart's YouTube videos of his HO "Gulf, Colorado & Santa Fe"
Norm Bruce's "Gulf, Colorado & Santa Fe"