I also think you should read the forums on Trip Advisor. I use them for all of our non-Disney trips. Using the nps.gov website, TA, and my big ol'
AAA driving maps, I can spend months planning a National Parks trip!
TA is great for lodging and IMO you can't beat AAA maps.
But IMO, for all things National Parks, check
www.fodors.com and especially their USA forum.
Type in the name of the National Parks in the search box and you won't believe how much information you'll receive! Its like the DIS for National Parks!!!
Hey cowboy,
Let me ask you, is there some way to book Old faithful lodge. I tried last year for th is summer on the national parks website and it seemed every day was booked. Do you know how far in advance do they accept reservations? Can I call the lodge directly?
Call back daily. Hourly. You'll eventually get in. (most likely)
People booking Yosemite have this down to a science. Cancellations for that park go back into the system at 7am Pacific, so people check then! I learned about this on the Yosemite TripAdvisor forum.
LOL, ITA its a science! Like Disney strategies! For all the National Parks. The parks have become very popular again in recent years and after several visits, you do get it down to a science, similar to *doing* Disney

Again, go to Fodors.com for ALL thinkgs National Parks!!
But be sure you have lots of time; you could spend hours .... days reading there!!!
I live just outside of Zion and I would highly recommend adding that park to any itenerary involving both Yellowstone and Grand Canyon. )
Oh ITA !!!!! And you are soo LUCKY!
Zion Canyon is STUNNING!! So is Bryce Canyon! Each so different from Grand Canyon! (so is Escalante and Capitol Reef and on and on!!)
We know people who MUCH prefer Bryce and Zion, and once they've seen the Grand Canyon, have never gone back to the GC while returning to Zion and Bryce countless times.
Did I mention how lucky I think you are to live there!!!