Is it a gui button you are looking for? What desktop are you running? Gnome? KDE? other?
If it is KDE, the Find Files gui is called kfind. You can lauch it from a konsole, type kfind and press enter.
You can always add a desktop icon in KDE. Works much like windbloze. Right click on the desktop --> Create New ---> Link to an application. Fill in the executible information, and pick an icon of choice.