My friend recently picked up AGOT core set and our group really liked it. Now we are trying to figure out the best way for each player to have cards for 1 house each. We could split up the core set however only 1 person would have tokens, board and titles.

Do the deluxe expansion for each house make for a good stand alone deck or do you have to have cards from the core set? I know having the core set cards would make the decks better but do I have to have them to run a playable deck. Do they contain neutral locations? I know I could check but I don't really wanna go through every single one.

I would strongly advise that you buy enough Core sets for each player to have one simply for the plot selection that is provided.  There are key plots (Valar Morghulis for example) that would put you at a decided disadvantage if you did not have access to them.  And to answer your specific question, yes there are quite a few good neutral cards in the core box- some important events such as Distinct Mastery, at least 3 good locations (Street of Steel, Street of Sisters and Shadowblack Lane) and even a couple of good characters (Maester Aemon for example).