The "call the coach before hand" stuff is probably good advice, and I could type here and pretend that like I'd do it myself ... but I wouldn't. Hunt around on the net some. You can usually find rankings for your state. Be aware of any returning state champs or high placers tha twil lbe wrestling there. If you're in Kansas, you can find last year's brackets on the KSHSAA site, I think.
How you cover the thing will depend a lot on who you're writing for. A big-ish regional paper that will have an interest in the winning team no matter which team it is, then obviously focus on the winning team and the kids from that team that qualify for state. Open with the most exciting match that team had, or maybe a match really late in the tournament that ensured it would have enough points to win. Again, be sure to mention any defending state champs that punched their tickets back to the state meet.
If you're covering for a smaller paper with only a one or two or three teams you're interested in, focus on the kids that make state. Obviously any kid that would win his classification would be a big story, but you might find your best stuff in the consolation bracket. In Kansas, the top four finishers at regionals make it, so that match to get to the consolation finals will have a ****load of drama. For many of those kids, that will be their state championship match right there.
It's not hard to figure out the basics of the sport. Ask anyone for help: coaches, even the kids. I've said plenty of times "Hey man, sorry, I played basketball in school ... what move did you throw there?" or something. Be honest that you don't know what's going on. It will take a good coach or parent about 30 seconds to outline the basic stuff to you.
And the advice about just trying to slip in at the end and catch the finals, I think that's bad advice. You'll miss those consolation matches. I agree, usually they are boring as ****, but l like said, at the regional tournament with a trip to state on the line they can be high drama -- even more so than the championship matches. If the thing starts at 9, I'd show up about noon. It will probably run until three or four. That will give you some time to see the same kids wrestle maybe twice in the winner's bracket and give you some time to get up to speed on what the hell's going on and how the scoring works.
And take a book. And cash for nachos. It's a hell of a lot better to get there early and veg out in the stands with one eye on the boring early-tourney action than it is to show up midway through the finals round without a clue what's going on.