Websites:
1) http://www.hanguk.jp/ ...click on the ハングル講座 button at the top of the page to get to the lectures that are organized by level. You might have to register on the site to watch stuff, I can't remember, but it's free.
2) http://korean.nomaki.jp/site_j/study.html ...example sentences for grammar points and words. Click on 漢字語 also, there you can see a lot of kanji and words with their pronunciations in Korean and Japanese. There are links to other sites on the bottom half of the page also.
3) http://dic.naver.com/ ...This is a dictionary, but you can get plenty of Japanese<->Korean example sentences here too.
4) http://tatoeba.org/eng/home ...This isn't for just Japanese and Korean, but they have thousands of example sentences in tons of languages.
5) http://docs.google.com/document/d/1kSm64FxXmtAWgPImHXBsZ6npqP6VctYDzDlhBDrxGPE/edit?usp=sharing ...This is a Google document I made. The first half is basic conversational question & answer stuff and the second half is sentence patterns. There's English, Japanese, Korean, and French on there for all of the conversational sentences and English & Korean for most of the sentence patterns. I never got around to adding Japanese translations to all the sentence pattern sentences, but I checked the Korean sentences with native speakers, so they should all be good.
6) http://sites.google.com/site/nazonoikikata/han-geul/iknow/jc-1000-s1 ...More example sentences. These are the first 100 sentences on iknow/smartfm, if you know that site for Japanese and Chinese. I translated the first 100 sentences to Korean, also maybe 50 or so of the 100 sentences in step 2. I checked with natives for all of those sentences also, so they should be fine.
Books:
1)初級から上級まで学べる完全マスターハングル文法 ... a good grammar book with lots of example sentences. Look for it on amazon.jp, you can click the "この本の中身を閲覧する" button to get an idea of what it's like.
2) 昔話で学ぶ韓国語初級リーディング (for beginner), 昔話で学ぶ韓国語中級リーディング (for intermediate) ...I don't have the beginner book, but I have the intermediate one and it's really good. Basically there are fairy tales and on the side of the page there are Japanese translations for some of the harder words. After each story there is an explanation section for some of the grammar points in the stories. There is also audio.
Other:
1) Anime and other tv shows in Japanese with Korean subtitles. Have the video on one side of your screen and maybe the Naver Korean<->Japanese dictionary up on the other side of your screen. Try looking for simpler words in the Korean subtitles that you might understand, like simple sentence connectors, cognates, or words you have recently studied. Pause the video if you see a word like that, look the word up on Naver, click print screen on your keyboard to capture the video on one side of your screen and the definition/example sentences on Naver, paste the screen shot in Microsoft paint and save it as whatever the word was. Later you can go back and look at the pictures like a slide show to review the words. For intermediate and advanced levels instead of looking for words you vaguely know or words you found in some word frequency list, you should be able to switch to looking for the words you don't know.
If you don't know the Korean title for an anime or show, just look it up on wiki and switch to the Korean page. To find an episode just Google something like 나루토 344화. 화 = 話
