Good start, and congratulations on quitting the bad and starting the good.
That kit is a fine start, and could easily serve you well as a power source for whatever attachments you want to use with it. *** (It uses the 510 thread pattern, the most common one) *** A good next step might be to get some good cartomizers, like the 2.0 ohm Boge. You also might want to try a "clearomizer", which is a cartomizer surrounded by a tank that might hold anywhere from 3.5-6 ml or more of juice. These give you the good taste you get with a cartomizer (better than eGo-type tanks [which I use right now]) plus the convenience of not having to continually add juice to a stand-alone cartomizer, where the key is to keep the absorbent material continually wet in order to avoid hot, dry, burned-tasting hits. The cartomizer goes right through the center of the clearomizer and has little holes or slots in it that allow the juice to keep the cartomizer constantly saturated.
You might also want to experiment with genuine Joyetech eGo-C (3-piece) cartomizers and Type A tanks. They're really pretty convenient and well-designed, and for what they cost, they're worth trying and learning about.
Down the road, you might want to consider a power source like the E-power that uses replaceable batteries and a replaceable switch, instead of the sealed type that you (and I) now have.
I'm about to hit the sack, so I'm just going to attach my current shopping list of stuff that I'm going to buy so I can lend setups to friends of mine who want to get started:
smoktek.com
14650 protected battery 6.99
14650 body 12.59 (the tube that holds the battery)
e-power 14650 cone 4.99 (purely for aesthetics)
e-power 14650 switch 9.50 (get the latest one)
boge 2.0 ohm cartos - 5 8.95
Smoktank 3.5 ml single coil carto 10.95 ("Carto" = cartomizer)
Ego Mega Dual Coil Cartomizers 3.19
10ml bottle w/ needle 2.49 (For filling certain clearmizers)
B-D syringes 5 & 10 ml (Ditto)
18-gauge needles (5) (Ditto)
esmokeronline
eGo-C bases 12.89 ("Cone" and "base" part of 3-piece atomizer section)
eGo-C heads (attys) 25.60 - 5 ("atty" = atomizer - the third piece)
cylinder cover 3.50 (mostly for looks)
eGo-C Type A tanks 6.99 - 5
overflow caps - Type A 1.75 - 5 (go on the bottom of the tanks - to use as spares)
rubber mouth pieces? 1.75 - 5 (Might help for sharing a PV)
8 x 6ml drip bottles 3.95 (Nice for mixing little batches of juice and doublers)
drip tips 4.95 (For use with cartomizers)
juice - various vendors (Backwoods Brew, Tasty Vapor, Pink Vision, Alien Visions)
(The reason that the E-power power sources [which most others would call a "PV", for "Personal Vaporizer"] are listed in individual pieces is that kits seem to be out of stock right now. I call it a power source because by itself it's incapable of vaporizing anything, but that's another thread).
Good luck, and if you have any questions I'll be checking in again tomorrow.
Enjoy your new life!