itschris will have way more tips for you than I will, and prime rib is supposedly more difficult to do right, but meat is pretty easy as he said.
Grab your steak, and learn about the various grades, prime being the best (and actually can be pretty hard to find, you gotta know where).
http://en.wikipedia.org/wiki/Beef#USDA_beef_grades
This is how I cook a steak, typically, though it's been a while.
Let the steak out at room temperature for a while if coming from the fridge.
I heat up a skillet/pan, no oil, until it's VERY hot (you can sprinkle a little water, and if starts dancing or instantly evaporates, you're good to go). Throw the steak on there, to sear the side so that the juices will be sealed inside. After enough attempts cooking, you'll get a feel for when it's done. Then flip to the other side to sear it as well.
You move a steak as little as possible, to keep the juices in.
You can turn down the heat once searing is done.
There is a test using the muscle between your thumb and forefinger as a reference, I think, to know how well done it is, but I just push down on the steak and know from experience. However, the most accurate, and in fact easiest for you, would be to use a thermometer. From a quick google:
* Very Rare Steak – 120°
* Rare Steak – 125°
* Medium-Rare Steak – 130° – 135°
* Medium Steak – 140° – 145°
* Medium-Well Steak – 150° – 155°
* Well-Done Steak – 160°
edit: my brother is a huge believer in slow cooking meats, which is a totally different way of cooking than what I described, whether in a casserole or crock pot or whatever. Over/under cooking by 1 minute at high heat can be very significant, whereas with slow cooking it is much more forgiving. Overcooking by half an hour when it's in the oven for 12 hours is not as much as it seems.
http://www.google.com/search?client=firefox-a&rls=org.mozilla:en-US:official&channel=s&hl=en&source=hp&biw=1680&bih=869&q=casserole&btnG=Google+Search#q=crock+pot&hl=en&client=firefox-a&hs=a9b&rls=org.mozilla:en-US:official&channel=s&prmd=ivns&source=univ&tbm=shop&tbo=u&sa=X&ei=CvrKTczYBsXSiALb-oiZBQ&ved=0CJ8BEK0E&bav=on.2,or.r_gc.r_pw.&fp=64cfe6251a34cfaa&biw=1680&bih=869