So I'm stuck with incredibly tight hamstrings - and, I've come to suspect, hip flexors.  As noted in a response to the hammy exercise question, I can't even do single-leg deadlifts.  And I admit it, I don't really know how to stretch my hamstrings properly.  Is what runners do (put a leg up on something and lean forward) the best I can do?  Likewise for hip flexors, I don't know how to effectively stretch these muscles.  I google search suggested I get into a lunch position and lean back, essentially trying to touch my rear foot with my hand.  But this doesn't seem to be stretching anything discernible.

Any help would be appreciated!  Thanks.