Wow, this is an old thread. But I came across it, so maybe someone else will as well.

I found a really good website for practicing　JLPT1 grammar and vocab. Here's the link to the grammar exercises.

http://www.n-lab.org/library/mondai/test.php?mode=html&dbupdate=0&target...

The exercises are in more or less the same format as the test, and there are stats to let you know the relative difficulty of each question - ie., you can see what percentage of test takers got this question right.

Haven't used it much, but it looks really nice, and it looks like there's tons of other good stuff on this site.

Thanks, the site is more than enough..maybe too much!, but then these sites often are. the book looks like a good recommendation too so thanks again.

If you're studying grammar, I highly recommend this book, which includes all of the 1kyuu grammar:
どんな時どう使う 日本語表現文型辞典

As for sites, the best one I've found-- and possibly the only one you'll need, especially if you have the book I note above-- is http://www.nihongo2.com/toppage.html

Among the many interesting things on the site, there is a set of example sentences that covers all of the 1kyuu grammar, and reading and grammar practice questions.

The site is all in Japanese, but since you're studying for the 1kyuu, that should be no problem.