Check out http://backfitpro.com
. If you can get your hands on one (or both) of those books I think you'll be on the right track.
For me, I was constantly having nagging back pains/strains/pulls that would put me out of commission from anywhere between 1-3 days up to about 2 weeks...then having to bump weight back to ridiculously low levels.
It wasn't until I made a concerted effort to make lower back and ab work a focus that I could no longer ignore. Yeah, doing 'core' work sucks, it takes time that I feel like I don't have and let's face...it's boring as hell. BUT, it keeps me on track! I've learned that I have no option, but to include core work almost every day.
The most noticeably beneficial exercises (for me at least) was to start doing lots of side and front planks. I really hate doing side planks...but there benefit far outweighs their sucky-ness.