You can use notepad to code powershell if you want. A tool called powershell ISE comes installed with powershell. There are a number of third party tools available for free to expensive. They just released powershell tools extension for visual studio. It’s up to you, really.
Powershell 2 comes with windows 7, powershell 3 with 8, 4 with 8.1, 5 will come with windows 10. you can upgrade to the current version by installing the current windows management framework. Powershell 2 is the latest available for install on XP, that is if they haven’t taken the download down.
I can suggest the powershell 3 mva. It is good. I’ve heard many people suggest powershell in a month of lunches, although I’ve never read it.