There are few jams here in the greater Vegas area.
We have an Old-time fiddle jam on alternate Saturdays and Wednesdays, they are held in Henderson area. You can review the schedule of these jams and some others at Nevada Old Time Fiddle January Newsletter. The schedule is on page 6.
Also there is Southern Nevada Bluegrass Society jams on Tuesday nights in Henderson. I haven't gone to one of these for a year now but you can call their hotline at (702) 564-3320 to see if they are still having their weekly jams.
Not sure where you will be staying but Henderson is about 1/2 hour from the strip.
You can email me email@example.com for any further information. Let me know if and when you will be attending one of these jams. I'll see if I can meet you, schedule permitting.
Las Vegas, NV
"Every day brings a chance for you to draw in a breath, kick off your shoes and play your mandolin."