Season 3 + 4

Where can I find or buy them? All seasons were literally on iTunes and Amazon like a week ago and then *poof* they were gone. Now I can only find seasons 5, 6, and 7. I watched 1 & 2 on Netflix and I was really hoping to catch up completely so I could watch the current season on E!. Does anyone know where I can find 3 & 4 to watch, please?!! I swear I've scoured the internet and all the old sketchy links from watch online sites are dead ends :( I'm desperate haha. Thanks!