Oooh. E-cigs are my latest favourite hobby! I quit smoking 11 weeks ago with these.
Don’t bother with the ones that look like real cigarettes. In the long run they’re more expensive because they all have unique cartridges so you’re forced into buying just one brand (usually with nasty, poor quality flavours). Go for an interchangeable, refillable one.
A good one to start with is anything labelled “510”. This refers to the size of the thread that attaches the atomiser to the battery and means that you can buy spares from just about any e-cig supplier. (Atomisers don’t last long – you get a month or two’s use out of them before they start to taste burnt).
A kit like this would be an excellent start. A bit more expensive to begin with, but cheaper to run long-term.
Another good option is kits labelled Ego. These have bigger batteries which last longer, but they are heavier to hold and look less like a cigarette. This is the sort I use. Ego batteries will take both Ego and 510 attachments. 510 batteries will take an Ego-sized attachment only with an adapter.
There are also lots of options for the way of vaporising your liquid. Most kits come with an atomiser and refillable plastic cartridges which slowly drip liquid onto the heating element. You can also get cartomisers, which are atomisers wrapped up in wadding; the liquid soaks into the wadding. Or you can get clearomisers and tanks, where the atomiser is inside a tank of liquid; these are what I prefer.
When you buy your liquids you can get them in a range of nicotine strengths from 24mg (for heavy smokers) down to 0.