Q:

Do I need to reinstall Django for new virtualenv? 

Using virtualenvwrapper, I installed Django for one virtualenv.  Now I can't reach it outside that environment.  I want to be able to start new Django projects both outside any virtualenv, and inside new virtualenvs. 
Do I need to reinstall Django or can I somehow import the installation from my first virtualenv? 

A:

I would recommend just starting from scratch with a new virtualenv.  That is the reason that they are built: one virtualenv can house a project that uses one version of Django, but another project can use a separate version of Django (perhaps an older version because an app you're using doesn't yet work with the newer version). 
If you are attempting to completely recreate the same environment (probably because you want to run the project in another spot), you can use the pip freeze in alexcxe's answer.  This will install everything again from scratch, attempting to install the exact same version.  You may or may not want to do this, for the reasons I mentioned in the first paragraph. 
This is the entire point of virtual environments.  I have 20 different projects on my computer, each with their own virtualenv.  It's fairly common to work in this manner.