They come in sterling silver, or gold, and even leather. Most people start with a silver bracelet and add charms. It depends on what you want to spend.
Most people prefer this one to the lobster clasp one, which is cheaper.
http://www.tiaragalleries.com/tiara/product.asp?s_id=0&prod_name=Pandora+Jewelry%2D+7%2E1+Silver+Pandora+Clasp+Bracelet&pf_id=PAAAAAPOGOIBOGCO&dept_id=9611
They don't come with charms. You need to buy those separately. Beads are threaded on, and there are two threading areas on the bracelet as well. My brother bought my mom a bracelet with two beads, and I bought two special "clip" beads that cover those threaded areas. Beads start around $30 and can go up to $500 or more if you buy solid gold.
One important thing: the silver jewelry is coated with something, so it is tarnish free. But that also means you really shouldn't clean it at home, at least not with typical silver or jewelry cleaners. Definitely talk to the jewelers about how to care for them.