I don't really know sites, books etc for beginners but there are some ways I practice my Korean. I'm not a beginner anymore, but I dont' really know how to continue studying really however, thereis a site that I sometimes use to practice my korean knowledge. www.gasazip.com. It's not a learning site, but a site with Korean lyrics to songs. So I sometimes search for songs there and try to see how much I can understand from it.
I also read Korean children books and with a pencil I underline the sentences I can understand. And I use nldic.naver.com really much. Recently I download an app called Korean listening practice. It's suitable for beginners and advanced. There are short dialogues on it and broadcast from the KBS news. It's good to listen to, but I could only download the newsbroadcasts which is already advanced level and not the conversations.
I hope this is helpful to anyone .