Save on Accommodation

I was not believe when my friend told me that she manage to find many great offers from the hotel in las vegas. According to her, she could get at least 30% discount. 30% is quite many already. If the hotel rate is $300 per day, with 30% she could save $90 already. $90 is not many but that already could pay for 1 person meal per day. I think it does affect the budget of traveling. I hope I know how to find cheap hotel rate. So that I could save on accommodation when go travel also.