Here are a few tips on how to get discounted hotels and comps in Las Vegas.

Most Las Vegas casino/hotel websites have an option where you can either a) sign up for email notifications and/or b) join their player's club. So well before going to Vegas visit the websites of any hotels/casinos that you think you may go to while in Vegas. If you are not sure which ones you may go to, sign up for notifications for all of them. 

The reason for doing this is simple...by doing so you are going to start receiving email offers for all sorts of specials, discounts etc. First and perhaps foremost you will get offers and notification of any discount or special rates. In addition you can get some free stuff like free cover charge/admission to hot night clubs etc. (some of these which you would normally have to pay $30-40 for). Sometimes you will even get notification/invitations to special events (ie CD release parties etc.).   If you sign up at Harrah's for that casino chain's Total Rewards players card, you will receive in your packet an application form for a credit card that also pays casino credits - and offers an extremely low rate as compared to other credit cards.  And if you use such a credit card, you're not tied to having credits expire if you don't get to Vegas at least once every 12-18 months (time varying by casino).  The credits you earn on all your players card accounts can be used to comp meals and rooms as well as the more flashy offers of free or half-priced or 2-for-1 show tickets, etc.

Bottom line: it definitely is worthwhile signing up for these notifications, you never know what you'll get and sometimes you get some great offers. 

While you are in Vegas make sure that you join the Player's Club of any casinos you visit. This will make you eligible to receive all kinds of goodies, freebies, discounts etc., in some cases even if you never play in the casino.   It will also allow you, in planning for future trips, to log onto the casinos' websites as a player's club member and give you access to calendars of special rates available in upcoming months so you can more economically plan your trips.

Most casinos will give you some type of incentive just for joining their club regardless if you play there or not. Typically the most common incentives are discounted or free meals, drinks, or shows. Some will even give you some free slot play (like $10). Sometimes its only a deck of card or a pair of dice. But, hey, its free so why not?

Also by joining the players clubs you will get special offers via regular and email, sometimes even offers for free rooms for a couple of nights. 

Sometimes the full benefits of joining a players club are not realized unless you are planning a return trip. For example after your first trip you get home and get an offer in the mail from a casino. But again most do give you something right upfront while you are there.

As mentioned you will be given many offers and discounts even if you don't play at the casino. However, if you DO play at a casino where you've got a players card the benefits only get better. 

If you play the slot machines, always be sure your players club card remains inserted in the machine the entire time you are playing.  Every spin on that machine adds credits to your card, and some casinos now allow you to use those credits directly to increase your playing time on the machines. 

If you play table games, always make sure that the dealer notes your card number anytime you play and, especially if you play a significant amount of time, that you ASK if you are entitled to any rewards, offers etc. Most often the casinos don't advertise or let it be known what you can get for free, or at a discount unless you ask. So don't be shy about asking, at worst they can say no. You may be surprised what you can get for free after a bit of playing. Bottom line....if you plan to play somewhere, and again, especially if you plan to play significantly, ask in advance, or at the early start of your play, what types of comps you can qualify for.  Sometimes they will give you a reward even if you haven't quite met the requirements. For example if you can get a free meal for say 4 hours of play sometimes they will give it to you after 3 or even 2 hours of play. Again, always ASK! 

Speaking of live poker, for all you poker players out there ... often the poker rooms offer some of the best and easiest-met comp systems in the casino. Many poker rooms will give you a free meal for 3-4 hours of play. Also many casinos will offer you a poker room rate on your room, which again usually you qualify for by playing 3-4 hours per day during your stay. Sometimes the poker room rate may only be 10% lower than the regular rate but more often its more in the range of 25-50% off the regular room rate. 

Many places also offer a "casino rate" on rooms as well. This is where your player's card comes in handy and this applies most often when booking return trips. When booking (directly with the hotel) tell them you are a players club member and ask if you are eligible for any special or discount rates. Often they will send you offers but also they are not always 100% up to date time-wise on sending out offers. So again ifs always a good idea to ask.  Booking from the casino's website often yields lower rates even if you are not a players club member; but, as stated above, with that card number you can access "hot deals" for players card members only and view calendars for upcoming months which will allow you to compare rates and select the best dates for your trip.

In summary (the short version):

1) Sign up for email notifications and/or club memberships for all casinos on their websites

2) Obtain a players club member for all casinos you visit (if you haven't already joined them via online; if you have and have not been mailed a card, pick up your card)

3)  Make sure you always ask if you are eligible for any discounts, comps etc.