Welcome!
You can use e-juice in many vaporizers simply by using some organic cotton balls from your local pharmacy (or cotton from q-tips, its up to you). I've done this plenty of times with a variety of ejuices (but haven't tried them on a Volcano). If you want, some people also use something called "degummed hemp-fiber' (sold by hemp traders) - it's supposed to add a more 'earthy' taste to the vapor. I'm actually interested in ordering some of this fiber to see how it compares to cotton.
Don't get caught up in the Volcano hype. It's an expensive 1-trick-pony, and no longer the 'best vaporizer' on the market.
Do yourself a favor, go to the plugin vaporizer section of this site and sort the threads by number of replies. Start working down the list of the most talked about vaporizers. You'll find quite a few options out there, many of which are half the price of a Volcano