Please note: this post relates to 11.04 only, if you are using a later version see the this post.

Some programs like the Eclipse IDE have to be installed manually they’re not available from the Ubuntu Software Centre. To add these to the launcher panel in Ubuntu Unity first you need to create a desktop file (Unity calls it a launcher), save it in the applications folder, then you can just drag it to the launcher panel.

Create the Launcher on the Desktop:

Right click your desktop and select “Create Launcher…”. The following window will be displayed

Enter the details of the program, change the icon by clicking on the icon and choosing an appropriate icon.
This gives you a launcher on the Desktop

Add the Launcher Panel:

Open your Home Folder. (if hidden files are not shown press Ctrl + H and browse to .local/share/applications. Drag and drop your Launcher from Desktop to that folder.

Now drag and drop your launcher from .local/share/applications to the Launcher Bar on the left on your Screen.

You can now delete your custom Launcher on the Desktop if it’s still there.

Enjoy…