What specifically are you looking for? The tournament or other stuff around Miami? I can help with the former, not so much with the latter.
I hope you already have tickets and a hotel/place to stay, because that time of year is spring break in Florida and accomodations go very fast, especially the ones in better locations at good prices. If not, staying in Coconut Grove is ideal, because it is just minutes from the tournament venue, across the Rickenbacker causeway, in a nice, fairly quiet setting on Biscayne Bay. You can shoot right up Bayshore Dr. in the morning, across the causeway, and into the main public parking area across from the Seaquarium on Virginia Key in just about 10 minutes from Coconut Grove, depending on the morning traffic. Of course, if you have a parking pass that gets you down closer to the parking area at the main gate, good for you, but those can run you more for the week. The public parking on Virginia Key works quite well, IMO, if you get there EARLY and plan strategically. They use buses and generally do a great job keeping them running constantly to keep people moving into the tournament site once people start showing up, and then at the end of the day, back to the parking area from the tournament. But if you dick around until 10 or 11 or Noon you will find LONG lines, especially on Friday, Saturday and Sunday. Get there early--no later that 9--and you should have no problem. First matches are at 10 on some outer courts on the early days, gates open at 9:30 if you have a Mastercard, as they will let you in a half hour early. The public parking on Virginia Key is 12 dollars per day and starts on Wednesday when the main draw play starts. If you go the first two days for qualifying, they will let you park at the main gate--still $12 a day.
I like to get in as soon as the gates open, pick up a copy of the daily schedule for a buck, and make a complete circuit of all of the courts to see who is out practicing, taking pics/vids. Then at 10:00, depending on who is playing, I will go watch a match or several, or keep making circuits of the practice courts looking for particular players. 10-11 is also a great time to grab something to eat, as the food court is pretty empty then. If you wait until 11:30-1:30, you can pretty much forget about getting a seat. Same goes for 5-7PM.
The tourney info says you aren't supposed to bring food, racquets, horns, banners or commercial recording devices. Or weapons (duh). I've seen people bring food. I think you can bring "snacks" as long as you don't bring in "meals". The food there is good but not cheap. Waters are $3.25 or 3.50 each, a hamburger is close to 10 bucks, so is a salad...like I said, it isn't cheap. Hit the Lindt tent as they give those away if you like chocolate.
Players are accessible for photos/autographs on the practice courts. You can get right up on the fence if you want (and assuming you are there at the right time and not trampled by a mob--I got gored by one rushing after Rafa a few years back) At the start of the tournament, there are 6 regular practice courts plus a number of other outer courts (4, 5, 7, 8, 9, 10) regularly used for practice, so you really do have do a LOT of walking to check everybody out. But it is exciting, because just for the buzz of a crowd you can sense who MIGHT be around the next corner. Last year I happened to catch Fed on 5, Murray on 4 and Djokovic on 7 all at the same time, and there had to be at least a thousand people back there watching them practice. When I went around to find a large group around Ana Ivanovic on the other side, I wanted to get her picture but couldn't find a spot on the fence, so I casually mentioned that Fed, Murray and the Djoker were on the back side, and 75% of the people watching Ana cleared out and sprinted off, and I had a nice clear shot of her.
THe weather is nice there--usually about 78-82 on any given day and very BREEZY, only an occasional shower or two, but we've been lucky with rain the past few years. March is a good month for that. It can get warm up in the stands, especially on a court with stands/seats facing into the sun, so bring lots of sunscreen and a hat, and this may sound odd, but at night, on that island, it gets very chilly because it is so windy. If you stay for night matches you will freeze your butt off if you are not a Yankee--I can't deal with cold so I have to get a latte and buy a sweatshirt from the Fila shop if I am going to sit up in the stands on stadium court at night down there.
Which brings me to seats/tickets. Any stadium ticket will get you into any court on the grounds on a first come first served basis. I am not one to follow the "name" players much so I could care less about watching day matches in the stadium, so I buy a 400 level (i.e., top level seat) in the stadium and use it as a grounds pass to watch matches on the outer courts and in the grandstand court all day--the Grandstand is the second biggest court--a mini-stadium. They do not sell grounds passes unless and untill the stadium sells out, and also on the 1st 2 days, when there are no matches in the stadium. If you are going to stay all day and watch both day and night matches on any given day, buy a daily double for that day as you get a discount, usually like 10 or 15 percent off the total price for both tickets.
If you don't care about seeing the stadium matches, a slightly cheaper alternative is to buy a grandstand ticket, which gets you a reserved seat in the grandstand and access to all other outer courts except the stadium.
I think that's a pretty good primer for anyone going to Miami, but if you have other questions, just ask, and I will do my best to answer.