Where you source your materials depends a lot on the type of Jewelry design you had in mind. If you are making a one off piece for a special occasion such as a wedding you may want to use pearls or other gemstones so should contact a reputable gemstone bead supplier. If you are designing a piece for someone else you need to keep their coloring and bone structure in mind. Some woman can carry a necklace made from oversized pearls while on others it will just look ridiculous.
But not everyone wants to start with expensive materials. In fact some people want to design jewelry using every day items such as nuts and bolts found in a toolbox. If you are into recycling and want this to feature in your jewelry design you can find plenty of materials on your local beach or a yard sale. You may have to go through a lot of rubbish before you find the perfect pieces but at least you know that no-one else will be wearing a similar piece. If you have a local charity shop you could tell them that you are a jewelry designer and would be interested in any old or broken jewelry items that get donated. You never know what gems you may be able to pick up.
The whole point in creating your own designs is that you get to choose what materials you work with. You are not following someone else’s pattern so you don’t have to work with antique beads if you don’t want to. This gives you total freedom to go hunting for the raw materials wherever you like. Most people won’t be interested in scavenging their local beach front for treasure but you can find beautiful stones and pebbles just waiting to be incorporated into a fantastic jewelry design. It is also good for your health to get a blast of sea air into your lungs!