I really enjoy a Filipino group lounge act at the Plaza downtown. They put on a great free show.
The bar near the back of Bellagio (towards the poker room and sportsbook) has a great jazz band after 10 pm Friday and Saturday.
The New Frontier has a cowboy bar with a bucking bronco and live country music. There is some combination wet t-shirt contest and bucking bronco riding thing they do. The music is good if you like country.
I also enjoy a duet group of a woman and man who stand at the entrance to Excalibur (inside the casino). It isn't in a lounge or anything, but he plays the stand-up bass and she plays the violin. They are quite good.
My side of the family is into jazz and blues so we will check out the Bellagio and their group,as well as the Plaza band downtown for their cover songs. Cheapo Vegas likes them also, if I remember correctly.
On the other hand, the relatives from Reno who we are meeting in Vegas are definitely country and western fans, so looks like the Frontier has that covered.Wet t-shirts/bucking bronco/live country band? That ought to get the crowd lathered up pretty quickly!
Come to think of it, I remember a line from Peter Griffin in 'Theory of Blackjack' where he mentions "sitting at the Frontier bar sipping some white wine and listening to the better of their two country and western bands". Sure miss that dry humor and amazing math insight from his pen.
Always a good dance bands at Cleopatra's Barge at Caesars Palace. Make sure that it isn't an off night where they have DJ's sometimes. Also there is a great band called Boogie Knights. They play 70's Disco and are all excellent musicians.
If you like Rock and Roll the best local band that plays Rock is Yellow Brick Road. They play everything from Yes, Zeppelin, Arrowsmith, some Elton John,Hendrix ect.. Top notch players. They play at Suncoast, and Boulder Station as well as a couple other places.
At the Bellagio they have good bands in the Fontana's lounge. Check out Denise Clemente good Top 40. Harrah's has excellent live music outside in their open air bar the Carnaval Court as well as good bands just inside the door. House of Blues has Boogie Knights on Sat's. Also check Rain at the Palms as they have special nights of Live music. The band in the Ghost Bar upstairs is also good.
Holiday Inn Boardwalk has "Purple Reign" the Prince Tribute. For jazz there is Lon Bronson's all stars who play late night at the Riveria on Sat nights. Loveshack is a good band that plays at Texas Station. When you get into town pick up the latest edition of "Whats On" magazine, it's free. Also check out on line LVOL.com then go to Las Vegas Show guide. They list all the bands in town. Also check out Pollstar which lists bands. Hope this helps.