I've just started crocheting with wire and have made a few bracelets and a necklace. Here are some of the bracelets:

The three bracelets on the right were crocheted with 24 gauge Artistic Wire and freshwater pearls or seed beads. I probably wouldn't want to crochet with anything heavier than 24 gauge. Lots of people use 28 gauge, but I wanted a studier bracelet.
I have collected several jewelry crochet books. Crocheted Wire Jewelry is one of my favorites. The instructions are clear and well-written. I like it that several of the projects are unusual and very creative. I especially liked the cube pendant and the earrings made with tiny stitches. Every time I look at the book I get ideas for my own designs. The hairpin lace designs are gorgeous.