Take it easy.

It's overwhelming at first, and the basics are all mixed in with the advanced stuff, but the basics are simple.
There are a couple of models that are very popular with newbies and gurus alike, that most people like.
The Kr808D-1, and the Joye 510.
My first e-cig was the Kr808D-1 (Kr8, henceforth), and I love it. Cartomizers are relatively simple to get used to, and it has the best battery life of any e-cig in its size range. I also enjoy the way flavor tastes in cartomizers.
The 510 is a 3-piece system, with an atomizer and a cartridge. Same size range as the Kr8. A little more complex to get used to, but one of the best vapor producers around, and with a forum like this at your disposal, you won't have much trouble getting it worked out.
Either one will cost you about $35 for a starter kit. You'll also want to buy extra
juice. And that will get you going for a couple weeks at least.
You should also have spare parts - batteries,
juice, atomizers/carts or cartomizers, etc. But you can easily keep it under $100.
I spent $115 total, for a kit, extra battery, extra cartomizers, a charging case,
juice, and supplies for making my own DIY juice.
ElectrNicStix is where I got my kit, and they're great. They sell both the Kr8 and the 510.
MyFreedomSmokes has good juice, 510 kits, and DIY supplies - I've bought from them, and they're also awesome.