The best eras to visit were in the late 80s/early 90s. You could get a free breakfast (20 minute wait in line), $3 steak dinners, 25 cents primo German lager to celebrate Ballys 25th year etc) and rooms and buffets were dirt cheap. Now everything's at a premium price. Apart from Chinese or pizza buffets ($9) an evening buffet at a decent casino will come to $25-$30 + drinks and room prices are sky high (more on Friday/Saturday nights).
Still worth a visit though and Downtown (Fremont Street) is less expensive than the Strip. Best tip is don't gamble - the house always wins. Good tips are day trips from Vegas (Valley of Fire, Mount Charleston - skiing in winter, Red Rock canyon, Hoover Dam and Lake Mead) as well as Grand Canyon flights.