Bill's is easy to identify because of the demon head.
Bill's sword was a sword made by Hattori Hanzō for Bill, a former student of his. Bill's sword is first seen in Kill Bill: Vol. 1 while he is calling Elle Driver to call off her mission to kill Beatrix Kiddo while she is in her coma. In Vol. 2, Beatrix notices it sitting on a rack above his T.V. when she sneaks into his hotel room. In a deleted scene, Bill is seen using it, killing four armed men as seen here.