There is a wealth of information on this site regarding ways to increase your felxibility and mobility. If you look on the left column of the T-Nation page and scroll down to the blue box for article library you can click on it, then go to the bottom and click on “authors” you can look up these articles (listed by author).
John Paul Catanzaro
Stretching for Strengthening Pt. 1 & 2
Mike Robertson
Hardcore Stretching Pt I & II
Mike Robertson and/or Eric Cressey
Get Your Butt in Gear Pt I & II
Feel Better for 10 Bucks
Neanderthal No More
All of these articles cover stretching, active dynamic warm up, strength and or postural imbalances, myofascial release techniques, etc. All of these methods really work and will benefit you whether you are a bodybuilder, powerlifter, athlete in any sport, or you just want to be more mobile.
I would also suggest the book “Core Performance” by Mark Verstagen.