That can't be answered without a specific purpose in mind. Generally speaking, brass cased rounds are more desirable than aluminum or steel cased rounds. For plain target ammo, personally, I used Winchester white box and CCI Blazer brass.
Yes. The A5 acually works better with high brass though.
Steel casings are used.
Yes, there is quite a bit of Russian steel cased ammo on the market.
There's no reason you wouldn't be able to, although you might not be advised to mix brass cased and lacquer coated steel cased ammo together.
Brass jacked hollow points
Through extrusion and forming dies.
lead, brass, priming compound, powder
Brass cased Wolf products from the Wolf Gold line come with Boxer primers and are reloadable. Steel cased Wolf products (like Military Classic) are not reloadable with standard reloading equipment.
Academy Sports discount full metal jacket target ammo. I believe it is made in Serbia. As of 9/25/09 their steel casing was selling for about $9.00 a box, and their brass casing was going for about $11.50.
Most 9x19 (also known as 9mm Luger or 9mm Parabellum) loads will cycle through a Glock just fine. It's always recommended that you use brass cased ammo rather than steel cased, but that holds true of most firearms.
Ammunition that uses a metal case. other than brass