I am very new to the game (though not the book series or lore). Actually, me and some friends are planning our first official game tomorrow! My question is this:

If I leave a Power Token on, say, Winterfell, Can I then later use a Consolidate Power Order in that area? I am aware that at least one unit must be present in an area for it to be considered yours (and therefore able to have orders), but in the rulebook it also says Power Tokens may be placed to assume control (including levieing taxes, etc). I read this as being able to muster, recieve supply, and consolidate power in that area regardless of unit staffing. Am I wrong? 

Thanks in advance for the help!

Cheers

So first a direct answer: No, you may not place a consolidate power order (or any order) in an area with no units.

However you can place a power token in an area when you march your units out and then it is controlled by you until someone else marches in.  When you control an area with crowns, you get one power for each crown when the game of thrones westeros card comes up.  This is similar to consolidating power there, but not quite the same thing.

The other benefits of controlling an area: you control the castle for the victory point, you can muster there when mustering comes up, you get credit for barrels there when supply comes up, you may have ships in the connected port, and other players may not retreat into the area.

I'll also point out that Winterfell (and each of the home territories) has a power token of the house printed on the board.  So Stark does not need to place a power token in that area to control it.  (Though another player who captured Winterfell could march out and put a power token on top of the printed one to override it).

Seconded. Everything dypaca says is how my group interpret the rules.