Lots of other threads about similar issues, but none that I could find where quite the same case as mine. So, here goes:
Things I did:
I've managed to get this working after having the same problem you've described here by editing my ~/.bash_profile and adding this:
export WORKON_HOME=$HOME/code/.virtualenvs
export PROJECT_HOME=$HOME/code
export VIRTUALENVWRAPPER_PYTHON=/usr/local/bin/python
export VIRTUALENVWRAPPER_VIRTUALENV=/usr/local/bin/virtualenv
export VIRTUALENVWRAPPER_VIRTUALENV_ARGS='--no-site-packages'
source /usr/local/bin/virtualenvwrapper.sh
Save, close.
then:
$ source ~/.bash_profile
and:
$ mkvirtualenv test