How do I grab the source code of a package

[tehhh1337]

How would I go about grabbing the source code of a package. For example, the top bar. How would I download the source code to that and then edit it?
Thanks

[blackbird34]

Well, you'd need to find out the package name for whatever runs the top bar. I presume you are talking about the Unity top bar: getting the source for the whole of Unity would be overwhelming, and I'm not sure if all the elements of Unity are all separate packages or not.

To get the source code of a given package you do
apt-get source *package* (without sudo). You need to make sure you have enabled the "Source Code" option in your software sources, which you can find in the Software Center (Edit > Software Sources)

This question on AskUbuntu will give you a lot of information to think about: http://askubuntu.com/questions/28372/how-do-i-get-the-source-code-of-packages-installed-through-apt-get

Looking around in the Synaptic Package Manager may help you work out what you are looking for. If you haven't already installed it, it's in the Software Centre or else
sudo apt-get install synaptic. There is a search bar, you could type in "unity" without quotes and see what package descriptions fit what you are looking for.

EDIT: this question might also help you: http://askubuntu.com/questions/221899/how-to-download-source-code-with-apt-get