I agree with Kent that Joye 510 are the best dripping atties for beginners. Some people like to add a nice drip tip; I have one, but I still take it off when I'm adding ejuice--I don't like juice dripping down the walls of the drip tip all the way down to the coil--dripping directly on the coil gives you much more control.
If you just want one or two, I get mine from LiteCig--superfast shipping and great customer service:
Joyetech 510 Atomizer 5-Pack (2.3ohm) | DigitalCiggz.com
If you want to buy a bunch of them, this is a good deal.
Joyetech 510 Atomizer 5-Pack (2.3ohm) | DigitalCiggz.com
I blow mine out after use; soak them in vodka or PGA when the coils get dirty; and when the coil gets really dirty, I do a dry burn. That said, many experienced atty users advise against dry burning.
And a very quick tutorial--just in case.