looking for books on wave propagationdistributed parameter
 

looking for books on wave propagation/distributed parameter
any suggestions? i am looking for something with a little bit of intro for a newbie like myself.
i am familiar with the classical approach, where time is the only variable... but i am really interested in how to develop and solve for the wave equations for various elements(beams, columns, etc..) as well as solving the pdes.
thanks!