E-Liquids, yeah. This is a vapers favorite subject.
With hundreds of flavors to choose from, and all this PG/VG stuff, what do you do?
There a few things you need to know, nicotine level, PG/VG mix and flavor.
We are not going to go into flavor because this is an individual choice.
So let's just get started.
What does all this PG/VG 50%/50% and other stuff mean?

E-liquid is a mixture of varying amounts of about 4 different ingredients. Nicotine, PG (propylene glycol), VG (vegetable glycerin) and flavoring. Some liquids can have additional ingredients, but for the most part, these are the main ingredients to all e-liquid.

The amount of nicotine is dependent on the strength of nicotine in your e-liquid, but let's say it is around 10% nicotine. Somewhere around 10% of your e-liquid will be flavoring. That leaves 80% of the liquid in your bottle for fillers, which dilute the flavoring and the nicotine. This is where PG and VG come in, and depending on how you like your vape, that determines the percentage of PG and VG in your e-liquid.

Propylene Glycol (PG) is a much thinner tasteless liquid. PG produces more of a “throat hit” (TH) than VG does, which simulates the feel of smoking better.
PG also has a higher rate of sensitivity for some people, meaning that some people just can’t use PG in their vape.
The more % of PG, the thinner the e-juice.

Vegetable Glycerin (VG) is a thick, sweet liquid.
VG produces luscious clouds of vapor. VG also imparts a sweeter taste to your liquid.
Simplified, VG gives more vapor and is sweeter. The more % of VG, the thicker the e-juice.

So, 50%PG/50%VG is an equal mix of TH and vapor.

All Analog (traditional tobacco) cigarettes have nicotine. But did you know almost all vegetables have nicotine also? Yes they do. Nicotine is only one of the addictive ingredients in a cigarette (see our "Why E-Cigs" post). So weather you eat vegetable or smoke, you still get your nic.
Now I know what you're going to say, tobacco has a higher level of nicotine, ok.  and I say, but we still like it.
Now, if you smoke about a pack a day, I recommend (and this is just an unscientific measure) a liquid with about an 1.8% nicotine level which is 18mg. If you smoke more, go higher. Ans so forth is you smoke less.
OK, lets just say, your on your own. Everyone has different tastes. You may like something that I don't and visa versa. Find a flavor you like or 30, and never stop trying different flavors.
Keep in mind, there are many forums out there dedicated to help you along your journey.