Reinstallation of Pages

I have to reinstall Pages after my Macbook Pro crashed, and although I bought the Mac and software last year when I gave my my serial number Apple do not give me support because apparently it is over 5 years old, which it cannot be!. How can I install Pages quickly, freely and easily? I bought software and hardware legimitely but I feel cheated as the Macbook crashed without warning and I am struglling to reinstall the programs