Two resources I've found recently that I'm finding to be of good value. I'm positive they aren't "new", but I haven't paid much attention to them until now.
First is ClearanceJobsBlog.com which has a ton of questions and answers with OPM and contract investigators about security clearance issues, background checks, etc. I've learned some new things from this site.
Second if the Military.com salary wizard. If you haven't played around with this tool, it is facinating. It really makes you think about a career change when you dive into it.
I also found a good ebook on govjobsecrets.com that helped me land a job within DOD. Before I came across that ebook I searched and searched on OPM and applied to many jobs without much success. Good luck to everyone!