Post aimed mainly at groovejet and Inthebeginning, but is also a very simple guide for those who have been a bit overwhelmed by all the variety discussed on this thread. Experienced vapers either ignore, or check for errors please!
There can be a trade off to be considered around cost, variety, overall experience and hassle.
The cigalike ones are the simplest to deal with in that you just unscrew one cart & screw in another. These tend to be the type that you can buy at the local market or shopping centre for a comparatively cheap initial purchase, but the carts they use can be very expensive and tend to be limited in flavours/strengths depending on brand. They can be useful in that they are small, look the most like "real" cigs, and are the most hassle-free, but the experience really isn't as good as other methods and the cost is higher.
The next step is to have a battery and disposable tank type system (CE4 in my case) where you buy the different liquids and fill the tank yourself. The batteries last a few months to a year (about the same or a little longer than the cigalikes) and the tanks (clearomisers) last anything from a couple of weeks to a couple of months - this can be extended by cleaning, but the coils inside do eventually pack in. This method is much cheaper and gives a much more satisfying experience, but has the added faff of unscrewing and topping up the tank rather than just chucking the
You can then go further and use tanks that have replaceable wicks & coils, can be stripped down & "serviced" etc. There's also a lot of variety and complexity available in the overall set-up e.g. variable voltage batteries. All these add to the hassle factor but allow the overall experience to be much better fine tuned to suit the vaper. Cost is a moot point here - you will save money using serviceable tanks, but people that get really into this can spend a fair bit on shiney new toys!
When it comes to the "juice" or liquid there's a hell of a lot of different things to consider - nicotine strength, flavour, the balance of "throat hit" vs vapour etc. But basically there are 3 ways to get the right juice which are buy ready made from a big importer (limited options), buy made to order from a smaller supplier (needs to steep for a few days), or buy the makings & mix your own (hassle, mess & steeping). These have been ordered from minimum hassle/maximum price to maximum hassle/minimum cost.
I'm a naturally lazy person and comparatively new to vaping, so I have a battery & disposable tank system, and am currently buying imported juice (Hangsen pineapple and Smartjuice Red tobacco flavour) which I know has steeped plenty while being shipped over and both brands have very good quality control. I will probably go directly to mostly mixing my own once I get a bit more money at the end of the month to buy all the bits & base liquids, though will probably continue buying the Smartjuice tobacco flavour because I like it so much! I doubt I will go down the road of serviceable tanks unless I get a nice glass one eventually.