I installed marlin file browser in ubuntu 11.10 but it have no search box is there any plugin to do it ? Is there any alternate search box for nautilus?
Marlin file browser is still in development and it means that you can miss some features.
Marlin can search files. but only on the folder that you are viewing, to do that you only need to type the name and then a textbox appear in the right botton edge of the program.
Do not forget to report bugs and ask for features in the marlin lauchpad to help the project.
Other option is to write a plugin but i don't know if there are an api or something to do that.