welcome to the board. The first thing I would do is check to see what is provided for you at the local gym. In most cases, all you will be required to bring is your own handwraps. Many gyms have racks of gloves that you can use for your workouts. Just wear something cool and comfortable, and bring a set of handwraps with you your first time out. If the gym does require that you bring your own equipment, I suggest picking up a nice jumprope to warm up with, and a quality set of bag gloves. They should be between 10 and 14 oz's. I usually use either 10oz or 12oz gloves. The lighter gloves are closer to the actual fight weight, but the heavier gloves offer more protection for your hands, and a little more weight for a tougher workout. Since youll be putting in alot of time with the gloves, get a quality leather pair that will last you a long time. Ringside, Title, and Everlast offer some very nice gloves, but stay away from the low end Everlast stuff. If youll have a trainer or assistant there to help you, then lace up gloves are the way to go. They offer better wrist support because they can close tighter around the hand and wrist.
Here are a couple of the websites where you can get the pro quality gear: