Know what you want and don't want Before you begin your shopping think about what you want and more importantly what you don't want. I'm not a fan of jewelry, I'll wear a watch on an occasion but it's rare, so I knew I wanted something simple, durable, with no jewels. For me this ruled out the golds and the other soft metals and kept me focused on the look of the band and the metals that were in the running.
Browse around online This is easy, just do a quick google search for the metal type and wedding ring and you'll have tons of selection. If you are going to buy online you may want to have more discretion which website you are using, but to browse styles and what not, a google search should suffice.
Try on the contenders The best way to narrow the field is to actually try them on and see how they feel. Some metals are heavier than others turning the figurative ball and chain into a literal one.
Most rings regardless of metal have similar styles. If you find something you like in cobalt, chances are you can find it in Tungsten or Titanium, Gold, Platinum etc.