Pouches are another necessity. As period pants generally have no pockets, you'll need somewhere to put things. A pouch can be a simple drawstring bag, like a dice bag. Please, no Crown Royal bags (unless you're royalty and want to take the time to pick out the embroidered logo). Or it could be made of leather or fabric, with a flap to hold it closed. If you are particularly style-conscious, your pouch will match the rest of your costume.
Let's turn our attention now to weapons. First of all, unless you have been told to carry a weapon, don't. You may carry a short eating dagger, but anything more requires express approval from the directors. A discussion of which weapons are appropriate to the period is beyond the scope of this page, and will be dealt with on a case-by-case basis.
You will also need various hand props, mostly food-related. To begin with, you need a mug. Mugs may be made of wood, metal or leather. Avoid glass-bottomed mugs, for two reasons: first, they're not Period, and second, they're more prone to leakage. If you can find a way to cover the glass bottom that does not look like you're covering a glass bottom, go ahead. You will also need a bowl. This should be either a wooden or (if you are noble) metal bowl. Avoid the press-board salad bowls, but solid-wood salad bowls are usually fine. Of course, to go with your bowl, you will need a spoon. A small wooden spoon is ideal, or nobles may use antique-looking silver. Notice the absence of a fork. Forks were considered a sign of the devil, and were not used by the general populace. The nobility might have two-tined forks, but this is a new fashion imported from France, and subject to much suspicion.
Most of these items will be hung, at one point or another, from your belt. That's why a sturdy belt is a must!
More on accessories can be found here.
Here is a wonderful article on jewelry, including some advice on how to make your own.