For anyone arriving early, you don’t need permission to get on the field and throw. For LD, be sure you’re in the LD area. See map on the site. For other events, the Individuals area is fine, just watch for people.
As far as Texas and Dallas, let me just say that I’m a Native... a true native. Born in one of the old line hospitals, raised here, went to school here and lived here all my life. So I know the place pretty well.
Texas is big, we all know that, but it’s so big it has seven distinct geographical zones (topography and geologic differences). There’s the coast, as we’re all aware of recently, with hurricane Ike smacking Galveston, Houston and other cities and several of our boomerang friends. All appear well as of this writing. And the other zones are the piney woods of east Texas, the hill country around Austin, the mountains of west texas (yes, real mountains), the high plains of west Texas ( which includes the Panhandle and Amarillo), the swamps of far south east Texas between Beaumont and Louisiana and the rolling plains of the Dallas area. Though Wikipedia and other sources list things a bit differently, that’s what I learned in school so I’m stickin’ to it!
The Dallas-Ft. Worth area is also big. Locally we call it the Metroplex. It encompasses a large number of communities, including Mesquite, and the entire Metroplex area is about 60 miles in diameter. Though Dallas is part of Texas, many of the big cities do not resemble most of Texas. Dallas is an urbane big city and most of the residents aren’t from here. But we certainly have a Texas flavor. The Mesquite rodeo (though not occurring during the Nationals) is just a few miles south of the tournament field. But there are also trendy areas, similar to other inner cities, in the center of town and to the far north... I said resemble... this is Texas, y’know? I hope everyone enjoys their stay.