Depends on what kind of show you wanted to see.
Big productions:
The Cirque du Soliel shows. The easiest to get tickets for would probably be Mystere at TI (aka Treasure Island). O at the Bellagio used to be tough to get tickets for but I haven't tried in over a year and a half. There's a new show, Zumanity at NYNY that starts mid-Aug. If you do that, make sure you get the $190 love seats (for 2, so it's like $95 per person). Taxes went up so expect to pay even more for taxes (probably close to 15% or more now). Not sure if you can call it a CdS show but Celion Dion's show at Caesars Palace has that feel to it from what I heard.
Blue Man Group at the Luxor. Probably the biggest theater of all the BMGs in the country. Pancho seats recommended.
Mamma Mia at Mandalay Bay. If you like ABBA, you'll probably like this musical.
Lord of the Dance at Venetian. I saw it when it was at NYNY. Good entertainment, not sure if it's worth the price of the ticket. A similar show, Spirit of the Dance, plays at Golden Nugget.
Stomp has a limited run at the Aladdin.
Headliners:
Take your pick. Not sure if you can count on Celion being on stage for long unlike the others (Wayne Newton, Danny Gans, Clint Holmes, Rita Rutner, Siegfried & Roy, Lance Burton, and probably a hundred others).
Magic:
I prefer Penn & Teller (Rio) but they can rub people the wrong way.
Comedy:
Plenty of choices here. Stardust, Harrah's, Palace Station, Rio, Orleans, Greek Isles, Flamingo.
Dinner shows:
I'm partial to Caesar's Magical Empire (Caesars Palace). Tournament of Kings (Excalabur) is decent. Never had a chance to see Tony n Tina's Wedding (here at the Rio or elsewhere). Other shows may have dinner associated with it.
Showgirls:
I don't see them but you can see Folies Bergere (Tropicana), La Femme (MGM), Midnight Fantasy (Luxor), Showgirls of Magic (San Remo), X (Aladdin), Jubilee (Bally's), Showgirls (Rio), Skintight (Harrah's), Crazy Girls (Riviera), Splash (Riv), Bottoms Up (Flamingo), probably others. Not sure if you're into seeing Chippendales (Rio), Thunder From Down Under (Excalibur), or Men (Riviera).
Concerts/limited runs:
Joint at the Hard Rock, House of Blues at Mandalay Bay (along with the event center and summer beach concerts), MGM, Paris, Aladdin, Thomas & Mack, and probably a few other places to see bands or headliners. Lots of bands seem to come through town just living off their laurels so if you're a bit nostaglic for that 80s sound (give or take a decade), you might find them in town while you're here.
Bob