Can I just say that the posts here of late have not been good for my budget or my diet. I've been drastically trying to resist ordering a leg of lamb from one of my purveyors, and now I have to do steak too?

A good steak is more about the quality of the meat and less about how much you do to it. I may be wrong, but I like my steaks to taste like beef

especially if I'm spending the money to buy one.
The cut has a lot to do with the tenderness and the flavor of the meat. The more used the muscle is on the animal, the tougher it is going to be. Usually those meats are better suited to cooking for extended periods because the proteins really need to be broken down. That's why things like the legs, tail, etc tend to make great stew. For a steak though the desired cuts are from places that the animal doesn't exercise, like the tenderloin.
The way the fat is distributed on the meat is going to influence the flavor a lot. Fat is flavor. Fat is also 9 calories/gram as opposed to 4/gram of carbs and protein. A ribeye (my choice) has marbling throughout the cut, and tends to make for a very savory piece of meat. Tenderloin is prized because it has virtually no fat (and because they're a ridiculously tender cut).
So, my process (without doing it sous-vide that is):
First of all, my favorite way to cook a steak is in a cast iron pan on the range. As much as i love the grill, there's nothing that can come close to getting the flavor I want like this. So for my method, having a cast iron pan is ideal (and they're cheap, I paid 15 dollars for mine and that was 6 years ago. If you don't though, it'll be ok, you just need something oven-safe.
When you cook the meat, it's important for you not to cook it when it comes straight out of the fridge. There are arguments about when to season, but what I do is about 30 mins prior to cooking, I take the steak out and season it very generously with salt and fresh black pepper. Nothing else. I let it sit out on the counter so that the salt can draw some of the internal juices to the surface.
In the meantime preheat your oven to 450/500 F (232/260 C). Put the cast iron (or other oven safe) pan inside and let it heat (dry) with the oven. After about 30 mins there should be some moisture on the surface of the meat. Take the pan out of the oven, put it on a burner over high heat. Add a little bit of oil (just enough for a thin film) to the pan, and coat it. Add the steak and sear the first side. Depending on the thickness and the desired doneness the next step changes slightly. Basically though after a few minutes you're going to have a beautiful mahogany brown crust on one side of the steak. Flip it. If you have something like a bone in ribeye (yum) or a thick piece of filet you want to take the pan and immediately put it into the oven. If its thinner and is already about 1/3 of the way cooked, the you should finish it on top of the range.
Cook it until its just under the temperature you want (read below for a neat trick on that that I picked up on my first job)
Bring it out of the oven and put it on the range, and drop the heat to low. Take about 1 T of unsalted butter and 1 or 2 sprigs of thyme and toss it in the pan (the thyme will spit at you so be careful of hot oil). Tilt the pan so that it's on an angle going up and away from you, and scoot the steak to the top of the pan. Let the fat and the thyme collect at the bottom, and using a spoon baste the steak in that fat.
And that's it. Finally. Take it out of the pan (add some finishing salt like a fleur de sel or a lava salt if you have it) and serve it. If you want to slice it prior to serving, wait 10 to 15 mins to let it rest because the internal juices are flowing almost like currents inside and if you cut it before they settle then the steak will leak juices all over
Now for telling the temp of a meat, without poking it with a thermometer or cutting into it, the best way is actually to do it by touch. As everything cooks it tends to 'toughen' up slightly. The tougher something is to the touch, the more well-done it is. Poking into it with a thermometer or cutting just gives a place for juice to escape. The trick I learned was at my first job and it works well enough. After a while you'll figure it out and be able to do it without using the trick and you'll develop a real feel for it
Meat Temps by Touch
Oh, and the perfect steak...Bone-In Dry-Aged Ribeye, Cooked Mid-Rare w/ Sauce Bordelaise and Béarnaise