Just to the right of the "Juice" it searches this forum. example: click search, type "how to fill a cartomizer" you get lots of different posts and choose the one you want.
I would recommend,
Batteries: Vision Spinner 1300mah (powerful and long lasting VV batt)
Tank: Vivi Nova (easy to use and fill and I have add no problems with any of mine)
It's best to drain the battery till the light blinks or it is dead. Most of these batteries are good for around 300 charges so to get the longest life it's best to kill the batt then recharge