It's amazing to think that in modern times hamburger patties are a commonly enjoyed food. It wasn't that long ago that people dreamed of "a chicken in every pot", because most people could not afford meat.
While you can go for the fresh ground beef to make your burger, that only lasts 3-4 days in the fridge. It's about the same cost to get frozen patties. Not only do they last much longer, but you don't get your hands all gooey (never mind the counter) as you shape them into patties! The flavor is pretty much the same for the two.
You can toss the frozen patty right on the grill if you want, but it's good to thaw it out just a little first in the microwave. Otherwise you might end up with a burger which is pinkish in the middle while the outside is crunchy. For a frozen third-pound burger it's about four minutes on one side, then two minutes on the other. Your time will vary depending on the thickness of your burger and the meat's fat content. A higher fat content will cook more quickly.
You want to aim for a temperature of at least 160F within the burger for safety.
McDonald's actually uses frozen burgers for their meals. They fry the burgers, rather than grilling them. They use a cast iron press to ensure the meat is flattened down on the metal fully right when the meat first goes onto the frying surface. Part of their technique is to put a cover over the burger while it cooks to sort of steam them. They add a dash of salt and pepper.
Burgers are (hopefully) 100% beef which means they are all protein - there are no carbs at all in there. If you really must have buns with your burgers, make sure you look for low carb varieties - whole wheat or whatever else is available in your market.
Most condiments that people commonly use are REALLY full of sugar. Ketchup is pretty much red sugar water with a wafting of tomatoes. I highly recommend looking for sugar-free varieties of condiments. The flavor is pretty much the same, and there's no reason to be filling yourself with sugar in such a non-essential way! Chili sauce is another good alternative.
Many people have pickles with their burgers. Depending on the variety you eat they are about 1g - 2g per pickle. It's a great trade-off, because the pickle is full of nutrition for you.
Lisa Shea's Library of Low Carb Books