I'm no expert, but have been drinking wine for a while, for business and pleasure. Here is my advice:
Finding out "what wine you like" is an expensive and subjective process. Not only do you need to taste test a lot of grapes, regions, and winemakers, but your tastes will mature and change as you go along, rendering your previous knowledge incorrect. You can certainly start enjoying wines right off the bat, but you have to accept that some of the wines you buy on recommendation you aren't going to like, and that even when you find something you do like, you aren't experienced enough to know if this is as good as it gets, and if you should still keep trying new stuff. This is what makes wine drinking expensive.
The unfortunate truth is that in the average wine shop, most of what is for sale is swill. The rare bottle that is actually good wine at a decent price is snapped up pretty fast. When wine drinkers find a new "gem", they stock up like crazy. Eventually the brand figures out that the vintage is selling like hotcakes, and the next year's vintage comes out double the price, and may possibly try to produce far more wine than the winery can assure quality. This reduces the quality of the following year's vintage, and combined with the fact that it's very difficult for a winery to maintain quality from vintage to vintage results in following vintages being subpar. The search for the next "gem" continues and the cycle repeats. Let's take the case of the macon lugny les genievres 2011 white burgundy. I was an early adopter of this wine, it sold for 15 USD a bottle and I snatched up every case I could get. When 2012 came out, it was half as good as 2011, and now 30 USD. I never bought another. The exact same thing happened with cloudy bay sauvignon blanc 2011, its now barely drinkable.
It really pisses me off when I go to a restaurant and order what I know is a good vintage, and then the waiter brings out the following year (which I know to be shit). You might dismiss it as snobbery, but the vintage matters; it might as well be an entirely different label/product as far as I'm concerned.
How do wine drinkers find the next best thing? They buy a ton of bottles and taste it all and eventually they find something good. The fact that everyone knows it's a finite commodity combined with the inconvenience/cost to locate the good stuff leads people to seldom disclose what the good stuff is until it's too late. I think of is as the good fishing spot nobody ever tells about for fear it will get fished out.
Some general tips
-stay away from mass produced brands like E & J gallo, Orlando wines, casella wines, which bring us atrocities like jacobs creek, turning leaf, and yellowtail.
-stick to wines between 20 - 50 USD, this is the "value block".
-there is absolutely no reason to spend more than 100 USD on a bottle unless you are trying to impress someone. The increase in quality is marginal for the increase in cost.
-don't buy wine in shops that source from places that store the wine improperly (you will realize this with experience)
-if you don't like a particular grape, don't discount it entirely. Keep an open mind and keep try a different label, a different region, a different vintage. It takes a lot of trial and error.
-The best tip I can suggest is to find friends who really enjoy wine. Wine drinkers hate drinking alone, and they will share some incredibly awesome bottles with basically anyone willing to drink with them. This is how I got started.
My personal tastes for everyday value - I enjoy (in no particular order) pinot noir from yarra valley, white burgundies, red rhones, and tempranillo from New zealand. For rare special occasions that merit a first/second growth or similar quality, I prefer (again in no particular order) - chateauneuf du pape (E. guigal), baron de pichon, chateau haut brion, and montrachet.
