CAPPERS:
Cappers in use today come in two styles. The basic one is a wing type, which has two handles. After you put the capper in place, you push down on the handle, crimping the cap in place. If you purchase a basic homebrewing equipment kit, this the type of capper you will get (lowest cost option).
Moving up to a bench capper was the first equipment upgrade that I made. Bench cappers have a base that sits on your work station and an upright post which lets you adjust the height of the capper. The cappers operate with a single lever, and most bases have holes predrilled which allow you to secure it to a permenant location.
The bench cappers are very versatile. Mine will easily handle 1.5 L magnum champagne (style) bottles. I would recommend you purchase bench capper if you are sure that brewing is a hobby you will stick with. Choose the wing capper if you are just checking out the scene.
CAPS:
There are several options in bottle caps:
Plain caps with either a gold or silver tone finish.
Overrun caps (the cheapest) that are printed wiith a soda or beer brand.
Oxygen absorbing caps (most expensive) in gold or silver tone.
Take your pick. I prefer the plain gold tone ones.
If you use 12 oz. bottles you will need aprox. 54 caps for a 5 gal. batch.
For 22 oz. bottles you will need aprox. 29 caps.
For 750 ml. champagne (style) bottles you will need aprox. 25 caps.