Paulo,
Flying in that area you should get the Las Vegas sectional, Phoenix sectional, Las Vegas terminal chart, and the Grand Canyon SFRA chart.
Why would you want to take one of those boring sightseeing planes when you can fly it yourself? If you want to take friends (plural) you will need something a bit bigger than a PA-28 (warrior or archer I assume) to get high enough to do the Grand Canyon corridors. I'd be thinking C182 if I was you. Should be able to get one for around $100 or so per hour, maybe a bit more, I haven't kept up with those prices.