Actually, Syntax, the brain is a lot more complex and intricate than any machine or computer we can construct at present. There are literally billions of neurons in our brain (IIRC), they're naturally more efficient at transferring information, and as to the supposedly small size of the brain - its curves greatly increase its surface area, and thus probably it capacity to store information. So our brain has enough place to store our personality and sunconsciousness, more than enough actually, since we use only 10% of our brain's capacity (IIRC).

I also disagree with you on the topic of memory - it can't be social conditioning that causes it. There are people with photographic memory out there. How come they exist? Furthermore, why aren't there any speculations on this matter within the scientific community? Anyway, the real reason, IMHO, is that our conscious mind has limited "processing power" - we would be overwhelmed if every single image we saw, sound we heard, feelings etc. were stored in the conscious rather than the subconscious mind, research shows that the efficiency of the brain sharply decreases if a person is doing two tasks simultaneously, what would've happened if we had to hold thousands or millions of impressions at the same time? As to why can't we acess the subconscious at will - it's a defensive mechanism. The subconscious usually contains contens that are harmful and unpleasant to the individual.

As to the topic itself, I doubt that subconsciousness has some kind of specifically defined physical location in the brain. It's not something as functional or as sharply defined as vision or coordination - it's only a facet of our personality, which is the conglomeration of all the information we absorb since birth (plus a little bit of genetics). So no, it won't be as easy to point out. I'd say the pic Kaniaz posted is right on the spot.