If you want guests to be in a particular area (e.g. were all your expensive coasters are), put a "No Entry" sign in that area and everyone from all around the park will flock there.
To make a good ride, which the guests love, customize your own ride. Make the ride go straight up and then drop down, keep on doing that then make the ride come back to the beguining. It really works, the guests really like these rides which go straight up!
To get the "Chris Sawyer Secret Park", a massive theme park with tonnes of land and all the rides, plus the limited edition ride, the stainless steel line of doom roller coaster, go on to the mega park scenario and wait for 1 year, then close the park for 2 years but keep all rides and stalls still running, then set all the rides' prices to the minimum. This may be a big sacrifice but it does pay off. Then go back to the new game menu and you should see the Level "Chris Sawyer Secret Park".