Patti, of course you can use brass, and copper as well. These can be bought in sheets in various gauges (thickness of the sheet) in quite a lot of places in USA - retailers of stained glass, juwelry supplies, modelling (avia, ship, etc). These sheets can be cut into forms and stripes as desired with regular scissors for metal. Also some assortment of precuts is usually available - ready circles, ovals, etc but these are more expensive.
And may be it is better to start from brass and copper since these materials are relatively inexpensive (comparing to silver).
You will probably want lead-free solder if you want to make juwelry. Though brass and copper can be soldered with solders containing lead (as it is done in stained glass) and it is easier to deal with them since they melt at lower temperatures, you hardly want to wear a piece containing lead. Lead-free solders are also available from the same suppliers - Delphi glass has it for sure, Rio Grande as well, I suppose. They can advise you on the flux you will need as well.
Also you will need a portable butane torch to start with - an inexpensive one that is filled from these small bottles of gas for refilling gas lighters.
Also you will need something as a burnisher (to push the edge of metal towards the glass smothly and evenly and to lock the glass in the metal rim), files (to file the edges of metal), sanding paper of different grits (to sand and polish the finished piece). And some kind of finishing - patina, glider's paste, etc to protect the metals and create decorative effects though this is not obligatory right from the start and can be purchased later (copper can get shades of patina if you put your clean finished piece in a plastic bag with a freshly boiled egg free from eggshell and cut in 2 parts - there is enough sulfur to gently react with copper and develop natural patina).
Silver will need a different solder and may be flux as well. Both metal and solder are considerably more expensive.
Rio Grande seems to be a good place to start at. And on youtube you can find a lot of videos demonstrating how to cut, clean, bend and fit the metal parts to provide good conditions for the solder to "suck into" the joints and make them strong - it is really easier to see than to read. Just search for something like "solder bezel setting copper" (brass is pretty similar).
Good luck
