I'm a vintage Vegas fanatic also. I spend a portion of my free time researching Vegas history online when I can. Thanks for starting this thread. Perhaps I can also gain more knowledge from Denny Griffin.
Downtown is a good place to start with for vintage Vegas. There's alot more left up North. Fremont Streets name alone has alot of history, named after John C. Fremont who was a US Military officer, explorer, and candidate for the President of the United States. He was also a map maker and his maps made Las Vegas become and important stop on the way West. That alone is one of my favorite Vegas history facts.
I can go on in depth about alot of other things, but to keep it short some other historic tidbits and fyi's for Downtown which are my favorites are: The location of The Plaza, and Main Street Station which used to be where the first railroads through Vegas ran. The West wing of the Horseshoe (tower with the rooftop swimming pool). That tower was part of the old Mint Casino built in the 60s. The Fremont Casino, that was built by a famous architect by the name of Wayne McAllister who was famous for his unique Googie Style architecture. Built in 1956, 14 stories tall it was the tallest building in the state of Nevada. McAllisters other famous architectural works include Bob's Big Boy in California. He also drew up the plans for the El Rancho Casino (once located to the empty lot to the right of Circus Circus), The Desert Inn, and the Sands. Unfortunatley there's nothing much origional left to the Fremont that I can see except for its exterior shape Up North you can go even back further to when the Mormons first settled in town and get all that historic info. There are also some historic places still around. Forts, railroad houses, etc.
The Strip there's not too much 'vintage' left anymore. You can go to the Riviera. It's still got it's 2 original hotel towers from the 50s. It also still has the origional pool tiled beautifully with the old Riviera logo (still kept in great condition!). Circus Circus has a little history. It is the biggest permanent big top in the world. It was built by Jay Sarno who also built Caesars Palace. The Hilton has history besides being that Elvis Performed there. Built in 69' it was the largest hotel in the WORLD. It's creator Kirk Kerkorian then went on to built MGM Grand (now Bally's)which then became the largest hotel in the WORLD. Besides those tidbids he has an outstanding career history record that is very interesting. Tropicana still contains a portion of its original low rise structure from the 50s. The Frontier was a Howard Huges resort. Oh yeah I forgot, go back up North strip to that Korean BBQ joint (next to Peppermill). Believe it or not that was a casino called the El Morocco.
There's still a good portion of impressive history to sight see. UNLV has a great historical archive aswell that you can spend hours looking through and loose track of time.
Thanks again for starting this thread. I'm glad to see people in here that appreciate the towns history. Maybe if there were tons more people like yourself around that there would be more of it to see today.
If anyone knows about any more 'vintage Vegas' original sights around to see please do fill me in