Font Book has disapeared

Hi. Macforums has not let me down yet and now I have a serious (to me) problem. My application Font Book ... has vanished. I still have the fonts, but I have no way to organize. collect, and view them. As a designer type is one of my biggest tools and now I can not preview fonts to my satisfaction. I have heard of a similar problem on a diff board but without a resolution. I hope someone can help. Thanks guys.