I actually had this done just today, in fact! I went to a local spa that sells natural and organic makeup. You could get an hour-long lesson in makeup application for $75, but they will let you have the lesson for free if you buy $75 worth of product. Kind of a no-brainer!
I'm very glad that I went, because I don't know anything about makeup. I haven't worn makeup for probably twenty years, and even back when I did wear makeup, no one had taught me how to put it on, so I didn't do much (a little concealer on blemishes, a little clear mascara, some blush, and that was pretty much it). So I learned tons. Back when I was younger, eye makeup pretty much consisted of eyeliner, eyeshadow, and mascara, and a "natural" look wasn't considered all that important. Now there are a lot of blending techniques for the eyelid, where you don't even need to use eyeshadow per se but can use blush, highlighter, and other things. I would never have been able to figure that out on my own.
I wish I had known more about makeup before I had gone in, because I discovered that I should have asked for waterproof mascara--apparently the steam from having to breathe into my scarf when the temps are so cold made my mascara flake and smudge like crazy! But I called the spa, and they got in touch with the gal who did my makeup, and she said they have a water-resistant type I could try instead.
For me, the benefit of going to the spa was that the person who did my makeup knows me now, and I can call with questions specifically related to my own skin, and they can give appropriate feedback. And since they carry a few different lines of product, they can recommend whatever they carry that is best and not be limited to selling a single line.
The downside--but I think this will happen anywhere--is that you never know whether the same look can be had with other products for less. I ended up spending $175 on product, but I had to buy EVERYTHING, including brushes, since I had next to no makeup (I had only one compact). And the spa I went to carries only natural and organic lines, which are horribly expensive. But I can't do chemicals. The good news is that I need very little of what was recommended, so I would not be surprised if I can get a year's worth out of what I bought. And I am not the type to be changing my makeup up frequently, so a handful of high-quality pieces is all I need.
I think that in a perfect world, it would be great to go to a few places for a consult and then see which look you like best and also the price points and then go from there. I was limited because of the chemical sensitivities and also because of my lack of knowledge. But you have to start somewhere.