There are so many options when it comes to wedding bands: gold, platinum, eternity ... You should take your time picking the right one.
You can choose a simple, solid metallic band or something with a little more bling. Try on rings that you can wear with your engagement ring on the same finger as well as rings you can wear alone.
While diamond wedding bands are very popular, if it's not in your budget right now, choose a simpler style and wait till a big anniversary to receive the diamond one.
If you're having a Jewish ceremony, remember that you will have to exchange rings that have no breaks in them (meaning, no stones), so shop for, or borrow from relatives or friends, a pair of simple gold or platinum wedding rings for your ceremony.