A belt pouch large enough for a camera, spare film, and batteries will do. In hot weather, add a solid freezer pack to keep your film and camera cool, too.
Some manufacturers offer digital camera cases.
Many have extra loops for spare batteries and small pockets for memory cards, but they aren't as flexible as a regular camera bag. Many single-lens reflex camera kits include a basic camera bag. These will do, but as you add lenses and accessories, you'll need a larger bag.