3 monitor set up for optiplex 780

Hi Guys,

I have an optiplex 780 and 3 vga monitors (dell), I want to simply display three seperate web pages at the same time. I'm a total hardware novice and having read a few replys on similar questions am still sadly none the wiser. I believe I have three spare card slots and was told I could install a vga graphics card, which would give me a second vga outlet, but I'm unsure how to then connect a third for the final monitor connection.

Would be grateful for any suggestions, I use the web pages for match betting so odds change quite quickly during 'in play' matches  so 3 screens of info helps tremendously

thanks

Chris