This script will download the Technic Launcher from the techicpack.net mirror, install it into the shared user game directory, download a Tekkit icon, add it to the shared icon directory, and create a desktop icon for unity.
Open terminal by pressing 'ctrl + alt + t' on your keyboard.
type "sudo nano tekkit_launcher_installer" into terminal
type your password for sudo (same as your account password)
copy and paste the entire script bellow by right clicking and pressing paste in the terminal window (pressing 'ctrl + v' does not work in terminal).
press 'ctrl + x' then 'y' and the 'enter' button in terminal to close nano.
now type into terminal 'sudo sh tekkit_launcher_installer'
Type your password for sudo again (same as your account password)
After typing your password for sudo and hitting enter it will download the Technic Launcher, Tekkit Icon and install both into the appropriate share directories. It will also automatically create and install the Tekkit launcher shortcut into unity. The shortcut will show up in your installed applications on Utilities' 'Dash Home'.
Simply drag and drop that shortcut over to your launcher to add the shortcut, like any other program installed in Ubuntu.
Something to Note: One thing that might throw you off is that when entering your password for sudo in terminal, no characters will show up on the screen. This is a safety feature built into terminal to protect your password from being stolen.
Disclaimer: Please note that I am running Ubuntu 12.04.1, this might not work for other Linux installations. This has been tested on my machine and works. I am not responsible for any damage that might result from running or attempting to run this script.
#!/bin/bash
## Download & Installs Tekkit Launcher Program
wget http://mirror.technicpack.net/Technic/technic-launcher.jar;
mv ./technic-launcher.jar /usr/games
chmod -x /usr/games/technic-launcher.jar;
chmod 777 /usr/games/technic-launcher.jar;
## Download & Installs Tekkit Icon
wget http://rocketdock.com/images/screenshots/Tekkit-Icon.png;
mv ./Tekkit-Icon.png /usr/share/icons;
## Builds & Installs Tekkit Launcher Shortcut
touch /usr/share/applications/tekkit_launcher.desktop;
echo "[Desktop Entry]" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Version=1.0" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Name=Tekkit Launcher" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Comment=Tekkit Mod Launcher for Minecraft" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Exec=technic-launcher.jar" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Icon=/usr/share/icons/Tekkit-Icon.png" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Terminal=false" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Type=Application" >> /usr/share/applications/tekkit_launcher.desktop;
echo "Categories=Application" >> /usr/share/applications/tekkit_launcher.desktop;
chmod -x /usr/share/applications/tekkit_launcher.desktop;
chmod 777 /usr/share/applications/tekkit_launcher.desktop;