Gloves

Gloves come in two basic varieties (as far as Amtgard is concerned): Protective and Costume

Protective

In general, you can find protective gloves in most sporting goods stores. You might turn some up at a used sporting good store or thrift shop, but given the amount of sweat they soak up... well... Use discretion.

• Hockey gloves (street or otherwise): About as safe as you can get, but are clunky and lack fine manipulation. You certainly won't get one inside the vast majority of shield grips, and good luck drawing a backup weapon or throwing anything. They're usually ventilated to some degree but are still relatively warm by their nature.
• MMA/martial art gloves: There are a wide variety of brands and styles, with some common details. They're nigh-universally fingerless, and all have padding across the knuckles. The picture of Brennon on his wiki page shows a good example of what I'm talking about (there's also one in the background). Their open nature provides good ventilation. Some come with a bar across the palm that makes for a lousy sword grip but can be easily cut out.
• Generic leather gloves: while they might keep your hands from developing blisters or getting your knuckles scraped up, protective gloves are generally meant to keep ones knuckles from being battered and bruised... which is where this sort of glove falls short. They also tend to be rather warm.

Costume

Gloves meant to be worn outside combat. Decorative or for warmth.

Glove site