I assume that if you did a google search for Metatrader 4 it will direct you to a site to purchase it.
Do you have a forex account now?
I am at IBFX.(
www.interbankfx.com)
If you start an account with them(even a demo) you get MT4 with it.
A demo account requires no money, just registration.
Once you have your demo open you can play around using MT4.
As for the best indicators...there are many different threads dedicated to indicators and systems...many members are successful using completely different styles and trading timeframes...You have to figure out what style and timeframe is best for your personality.
I truly believe anyone can make money in this market, but it's not as easy as downloading and using indicators...it will take practice.