you really should read at least the review then of the book jay mentions - he goes through a ton of examples of where differences crop up between various versions of the bible and shows exactly how they were intentionally changed by scribes intent on solving specific theologic arguments going on at the time of the translation - interestingly, the changes required in order to push forward the argument were extremly minimal, oftentimes only a single word.
try 'Book of J', a translation of portions of the pentateuch by Rosenberg with an excellent intro by Bloom. demonstrates well the disparate sources used to construct the various narratives, and delves into the differing motives of both writers and redactors.
thanks for the tip - i'm not all that interested in bibilical stuff, truth be told, as , for me at least, it's akin to the genesis of the weekly world news - i'm a history teacher though, so i try to be broadly familiar w/ as much stuff as possible (well, that, and when i read that book i was trapped in hellacious virginia for a week w/ absolutely nothing else to read or do!)