sudo apt-get install gnome-alsamixergui
will not help too much as well, since it will still show only Master and Capture in the alsamixergui under Applications -> Sound and Video -> Alsa Mixer
So here is what you need to do: you need to install alsa from source. First, download the latest ones from here: http://www.alsa-project.org/main/index.php/Download. The volume control is under Utilities, but you will also need the Library to install that stuff.
So first, install the library:
tar -xvjf alsa-lib-1.0.20.tar.bz2
sudo make install
Then install the utilities:
tar -xvjf alsa-utils-1.0.20.tar.bz2
sudo make installNOTE - there is no make step here - direct make install!
If you get an error that says "`t-ja.gmo': No such file or directory" then you need to install gettext.
sudo apt-get install gettext
After that, once your utils are fully installed, go ahead and see the alsa in full glory: open Applications -> Sound and Video -> Alsa Mixer Gui and increase the Master, Head and Front volumes to full! Yennjoy!