Anne,
If I could tell you just ONE thing, it would be
juice. I know I didn't order enough juice from cignot. It's an inexpensive investment and I figured out that flavors I don't like can be mixed with other flavors or diluted, or just saved for an emergency. I really do not ever want to rely on "analogs" again - ever.
If I could tell you TWO things, it would be juice and another basic $35.00 starter kit. Since you aren't sure on which batteries you are going to prefer. Hold off and decide - then maybe order another basic starter kit. Extra batteries and attys will only help you not have to smoke analogs should something randomly go awry.
Before I received my kit I placed an order for e-juice with Ms. T's Bakery (they have some delicious sounding juice). I am hoping it ships quick! Check around for juice suppliers on this board - there are several highly rated suppliers with good prices and delicious sounding varieties.
I thought I would only want to "vape" menthol, since I've been a strictly menthol smoker from day one *cough* *ahem* years ago

but I am loving the cappuccino, mixing chocolate with cappuccino, mixing chocolate with Double Mint... why not enjoy *taste* along with the experience? It's pretty awesome!
I ordered the kit with the PCC and so far it's working great. It charges one battery while I puff on the other and holds 2 carts and the spare atty.
When I received my kit I realized that the mini USB cord included with the PCC is the exact same size as the cords on all my Canon digital camera gear, and the wall charger/car charger adapters I have for my iPod work with the USB cord from the PCC, so I can charge it in my car. I suppose it's all standard stuff.
Good Luck! Keep us posted!! Let us know how you make out and what you think when you get your new 510!!
Remie