Usefull sites for  Python:

Code Academy: https://www.codecademy.com/
    great to learn the basics, just need to follow the lessons


Stack overflow: http://stackoverflow.com/
    great to ask questions, has a ton of people with science/astronomy background (also visit sister sites stackexchange, etc)




Editors/IDEs:

Pycharm: https://www.jetbrains.com/pycharm/
    great, has code completion, auto ident, etc
    light-weight

Eclipse + PyDev: http://www.pydev.org/ , https://eclipse.org/
    Does everything you can imagine and more
    heavy :(

Spyder:     https://pythonhosted.org/spyder/
   
Geany:     http://www.geany.org/

vim:     https://wiki.python.org/moin/Vim