Excalibur is a great place to stay if you don't already have a hotel. It's one of the most reasonable places to stay without winding up in a dump. Take a night to just wander the strip with a giant margarita. The cheapest place to get a giant margarita is in front of the mexican restaurant inside of NYNY. Then wander outside and head towards City Center (Aria, Cosmopolitan, and I can't remember the name of a small high end shopping center with some interesting fountains). City Center is interesting to walk through, they have all sorts of interesting nooks and crannies, especially the Cosmopolitan. Make sure you see the gardens inside of the Bellagio and watch the water show. Along the hallway that goes behind the gardens there is a desert shop with a cool chocolate fountain. Next casino is Caesars, make sure you walk through there too. Walk through the casino all the way through the forum shops on the other end. It's basically a mall that ranges from normal shops to high end. Somewhere in there you will find a daiquiri bar that will refill those wonderful giant cups you've been carrying fairly cheap. Walk outside from the forum shops and the next casino you come to will be the mirage. They have a giant volcano out front, so watch that erupt. Next is Treasure Island which has a "sirens" show out front. Across the street is the Venetian which is another good casino to walk through. If you've made it this far, you'll probably be pretty tired and be ready to call it a night. If you hit all of those, you've covered the highlights of the strip as far as tourist wanderings go. Other casinos may appeal to you for places to gamble or eat, but they don't have any "must-see" features.
Don't forget that drinks are free when you're gambling, take advantage!
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As far as shows go, you can find plenty of mildly entertaining ones cheap. There is a half price ticket booth at MGM and a couple other locations. The best shows won't be for sale there. The best shows are some of the Cirque du Soleil like Ka, O, and Mystere.
If you're looking to gamble cheap, go downtown to Fremont Street. It's not as flashy as the strip, but they are doing a nice job developing the area. One side is called the "East Fremont District". At the end there is casino called El Cortez with $1 roulette
where you have 25c chips, $3 double deck bj, and $5 single deck bj. The also have a decent prime rib dinner that's like $8. And the drinks are still free.
I grew up in Vegas, and I've taken a lot of friends back. Even the ones that didn't think they would like it had a great time. The 2 things I always do with them is wander the strip and take them for some cheap gambling.
Everyone has a great time when they go to Vegas, don't worry too much about it, it's hard to go wrong there as long as you like drinking and gambling. Also, if you're spending your whole time on the strip, getting "deals" is an illusion, so don't feel like you need to waste your time on a bunch of research trying to get a "deal". It's just a bunch of people trying to take advantage of tourists one way or another. Food will be a little overpriced on the strip, don't worry about it. Just have fun. Oh, and understand you will lose every dime you go there with =). It's just one of the expenses of going to Vegas. If for some miracle you DON'T lose it all, it'll be a pleasant surprise. Oh yes, avoid the slots on the strip, they are tighter than a tick's.... behind. Especially on the weekends.