MasterBlogster scroll top and bottom plugin adds scroll button to your WordPress website to smoothly scroll to top and bottom areas.
Here is the
live demo of Master Blogster scroll top and bottom plugin
Plugin homepage:
http://masterblogster.com/plugins/masterblogster-scroll-top-bottom
Extract the zip file and just drop the contents in the wp-content/plugins/ directory of your WordPress installation and then activate the Plugin from Plugins page.