Welcome Darryl, Here are a couple suppliers of brass and nickel wire.
http://www.rjleahy.com/store/wire/bwi.htm
http://wire-sculpture.com/half-round...ss-wire-1.html
http://www.silversupplies.com/catalog/metals/
Stuller Inc. distributor of jewelry and jewelry-related products
Hoover & Strong - Soruce for gold and silver wire and sheet