You should look at audionetwork. http://www.audionetwork.com.
Its not library music that you have to pay for through the nose every time you use it. Its a licensed option but the quality is excellent and the range massive. All music is supplied to us on a hard drive with search engine, or you can download from the website with a login password.
Do take a look. if youre using library music you should look at it. We used to use library like you, and having bought an audio network license, havent had to pay for library since.