The closest Walmart Super Center to most of the strip is at:
3075 East Tropicana Avenue
Las Vegas, NV 89121
Pricing and services:
It's Walmart, you already know what they have, and since it's a Super Center, it's also a grocery store, so it's a one stop shop if you need to pick up party supplies, coolers, beer & wine, items you forgot to bring or realize you need. We used them for snacks for the wedding party, a full length mirror for my wife to have in the waiting room at our wedding venue for her to finish getting ready since there was not one, coolers for ice and booze, etc.
If you need liquor in addition to beer & wine, don't buy it at Walmart, go to Lee's for better prices.
People who have used this vendor (sorted by date) and link to the review: