Where to fly? Where do I start!
Anyway firstly I'll re-iterate those who have posted already.
Grand Canyon: Fantastic sights and photo opportunities.
Sedona: Stunning scenery but ensure the wind is pretty light... the airfield is on top of a mountain ridge.
Between Grand Canyon and Sedona (a little to the east of track) is the Meteor Crater that has been mentioned before.
Santa Barbara: Lovely picturesque airfield with a nice restaurant to eat at.
Monterey: Very nice town on the Pacific Coast. Nice fish dinners on the pier.
San Diego: I flew into Lindbergh Intl... one minute stroll from the FBO to the Tram system train station and about five minute ride along the 1.5 miles to the centre of San Diego... parking cost $20 (I didn't buy fuel).
Blythe: In the middle or nowhere. When I went two other aircraft from ADP turned up so it turned into a flyin.
Palm Springs: My dad was jealous as he loves golf... what more can I say! ;-) Beware of the severe turbulence that can occur late afternoon...
Big Bear: Nice restaurant, nice mountain ski-ing resort in the winter... they held the Winter Olympics there not so long ago (not sure which year though). About 6,500 MSL so please calculate your performance figures, especially after dinner!
Bakersfield Meadows: Nice ice creams at the restaurant.
Talking of ice creams, take a trip to Hawthorne airfield... two miles south east of LAX. Not sure where I would have gone if I had an engine failure after take-off! ;-) Probably the main highway next to the runway probably.
Chino: Plames of Fame museum. They also have a very good air show there...
Sacramento: (Executive airport is probably the closest) Nice old town area (north of the highway) with its own steam train and old style buildings, ie wild west style.
Catalina Island: 30 miles off the coast from Los Angeles. Airport on a 1,500 MSL moutain. Much is said about the approach and landing on the runway but it turned out to be much of a non event really. The take off was a little more interesting - taking off to the west you are going up hill and just as you get to the top of the hill the runway suddently runs out. ;-) Oh Buffalo Burgers!
Las Vegas: I've always used McCarren Intl... just because it is the closest to the strip - 5 minute walk!!! Well it turned into a 2 hour walk as we stopped into the restaurant half way along the road from Signature FBO to the Strip. Not much more I can say about Las Vegas apart from take plenty of money (don't go at the beginning of your holiday as you won't have enough money to buy the fuel for the airplane after a night at the Casino's!).
Above all enjoy your time flying over in the Western States.