I get most of my cards at prereleases; but I am first, a Professor; second, a collector; and finally third, a player. So aside from my strong sense of duty to the game, my main goal is to collect sets. As such, I cannot complete it by just the prerelease packs. I have also come to find that it is cheaper to buy full boxes than individual cards. So, I usually buy a box or two of the most recent set that my local card shop orders in for me. It is very sinergetic. I get my cards cheap while making it worth my card shops while to run a Pokemon League. They know if they lose the league, they lose my business (as well as the business of the other 3 people who buy boxes from them).