Here is my completely unqualified advice....
1) Go to HD (or wherever) and by the appropriate breaker (based on what wiring you used. 20Amp is you used 12AWG or 15Amp if you used 14AWG) (breakers protect the wiring).
While at HD, pick up this book
http://www.amazon.com/Wiring-Simplified-Based-National-Electrical/dp/0971977909
it's called "Wiring Simplified" and has a green cover. Go home and read it!
2) Wire a new GFCI outlet from the place you want it all the way up to, but not connected to, the panel where you want to add the circuit.
3) Hire an electrician to check out your work, and connect the wires at the box. That way you do the time-intensive work, and he will do the knowledge-intensive work.
FWIW, wiring can be scary, but is pretty straight forward. Doing it RIGHT is another story.
My house is loaded with tube and knob wiring. Also, in my workshop, it was wired T&K with an old Federal Pacific sub-panel.
I wanted to add a porch light to the workshop and looked for a Federal Pacific breaker. I found that they cost $30+ !!! So I looked them up online and discovered that Federal Pacific sub panels were DELISTED by UL!! As I poked into it more, I discovered that the panels and breakers were notoriously crappy. So I went to HD and picked up a SquareD panel/breakers, some 12AWG Romex and that Simplified Wiring book. I figured that, since the panel/breakers were crap, and the wiring was out-dated, I might as well re-do everything. Luckily, the workshop has exposed rafters and walls (no drywall. Yes, I know romex wire needs to be enclosed in drywall if it is within 8 feet of the floor). So I rewired the entire place. Learned a lot. The thing I learned most is that I hate T&K wiring!
Now I'm insulating my attic and have to work around tons of T&K wiring. I've discovered that whoever put it in there in the first place did a GREAT job. Every connection is done precisely and cleanly...sadly, the wiring is just old (house built 1939). And to preven fire hazzards, I need to make sure my insulation does not cover the wiring. Romex is SO much easier to deal with. (In T&K, the "hot" wire runs aroud and is spliced out to other circuits, and often the "neutral" wire runs willy nilly all over the place).
Anyway, I digress...
V