Some good tips from a post on Serious Eats for either sauteing or searing. I think I've gotten better at doing both.
Actually, the other night I did both: seared two grass-fed filets on the stove top in a cast-iron pan (that had preheated in a 400-degree oven for 20 minutes), finishing them in the same 400-degree oven for about 8 minutes.
Then, while the meat rested on the countertop, loosely covered in foil, I sauteed some mushrooms in a little oil and butter in the same cast iron pan over medium heat. Added some fresh thyme to the mushrooms, some salt and pepper, then when the mushrooms were getting soft, turned up the heat a little, added about 3/4 to 1 cup of cream, and let it reduce down/thicken for a few minutes.
Plated the steaks and spooned some of the mushroom sauce over each, accompanied by some asparagus (tossed with olive oil, salt, pepper, a good helping of lemon zest) that had roasted for 15 minutes in the same 400-degree oven. I oversalted the meat a tad, but otherwise it was really good.