how do I go about removing all the language packs I don't need

You can check which locales are generated and configured on your system using the locale command:

• locale ... list the current locale configuration
• locale -a ... lists all all locales that were generated on your system
• locale -a -v ... list all locales and show useful additional information (such as directory names that contain the locale information data files)

The last command from above makes you see that all generated locales are located in /usr/lib/locale/, you may remove any of them if unneeded. Each pack of locale information is a directory containing text files and other directories.

All locales that you want your system to support are listed in the text files in /var/lib/locales/supported.d/. These files have two columns, language tag and character map.

I want my system to know US-English only, so I have only one file there, called en, which contains just a single line:

en_US UTF-8

Error messages
If error messages are displayed when issuing the locale command, e.g:

locale: Cannot set LC_ALL to default locale: No such file or directory

make sure the file /etc/default/locale exists and has proper content, such as:

LANG="en_US"
LANGUAGE="en_US:en"

Get rid of unneeded locale data - Step by step

Now we know all the necessary details to get started with cleaning up our system's locale information:

1. Edit the locale file(s) in /var/lib/locales/supported.d/, and remove all unneeded locales (one locale per line)
2. Create and edit /etc/default/locale (see above for an example)
3. Delete all generated locale data: rm -rfv /usr/lib/locale/*
4. Re-generate new locales: locale-gen

That's all! Reboot your machine to make your changes take effect. Then run one or more of the locale command examples from above to ensure yourself that the result is as expected.

~# locale
LANG=en_US.UTF-8
LANGUAGE=en_US:en
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="en_US.UTF-8"
LC_NAME="en_US.UTF-8"
LC_ADDRESS="en_US.UTF-8"
LC_TELEPHONE="en_US.UTF-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=
~# 
~# locale -a -v
locale: en_US.utf8      directory: /usr/lib/locale/en_US.utf8
-------------------------------------------------------------------------------
    title | English locale for the USA
   source | Free Software Foundation, Inc.
  address | 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
    email | [email protected]
 language | English
territory | USA
 revision | 1.0
     date | 2000-06-24
  codeset | UTF-8

There is a package for Debian/Ubuntu that can take care of removing locales and locale related files (e.g. man pages):localepurge. You can install/run it issueing:

sudo apt-get install localepurge

once installed, you should run this:

dpkg --configure localepurge

to ensure your language settings are set correctly.

to run it manually once installed (although you shouldn't really need to as it should run after every dpkg run automagically) you can just do:

sudo localepurge

Read the man page before using it, though. If you can get your stuff done without it it's probably safer to let go.

from this forums

ref:
1. LocaleConf on official documentation
2. Linux man page
3. Locale on wikipeadia
4. man localepurge

As regards actually installed languages, go to System Settings -> Language Support and click the Install / Remove Languages... button. Then uncheck the languages you don't need.

As regards the symlinks in /usr/share/help, please see my comment on your question.