It always start with one gpu and ends with crazy farms. Goodluck with your first step , i am mining for 2 years now and still alot to learn , by the way i started with one GPU also 
I'm already planning my next gpu purchase. When this price dies down I'll grab some. I still have a ton of stuff to learn but my understanding of crypto and the mining process has increased substantially since I started mining. Good luck to you as well!
Would recommend grabbing some 560 4gbs, they're still roughly profitable and dropping in price all the time. They're about half the hashrate out the box of a 570, so if you can grab one for half the price you're in a good position.
Good work on getting the 480, I started off with an R9-390 I built with earnings from crawling through faucets
Thanks for the recommendation I'll keep my eye out for them. It's funny because I've always wanted to build a gaming rig and I finally did almost 2 years ago. I had no intention of mining with it but then I fell down the rabbit hole. Now I haven't used my gpu for gaming since I started mining.