It seems that the last DrupalCon in Szeged just happened, and the next one is already open for registration! If you haven't bought your tickets, you can buy them on the DrupalCon website. There is a limited amount of cheaper tickets (I got mine for $125!), so hurry up before they get more expensive. It also seems that the conference sites get better and better; registering was painless and browsing the different sections was incredibly intuitive.