Search & Play YouTube videos in Totem Movie Player / Ubuntu

First think to do is to install appropriate gstreamer plugins. Use the apt-get command:

$ sudo apt-get install gstreamer0.10-plugins-bad

Next, open up the Totem Movie Player. You can start it with the totem & command in the CLI (command line interface) or from the desktop menu. On Ubuntu it can be found under Application -> Sound & Video -> Movie Player. If you don't have Totem install it the usual way of installing software packages.
Under the player's Edit.. menu select Plugins... New window will pop and under it check the box next to YouTube browser. The new sidebar should become visible. Something like this:



It is also possible to install YouTube H.264 plugin for better quality. Download archive file from here, and extract the files in the:

/usr/lib/totem/plugins

enjoy.