i cook a lot of steak, so here's my advice.
buy a powder marinade from the grocery store, or if you don't want to bother marinating it, use emeril's steak rub.
cook
it in the broiler, and there isn't a huge difference.  cooking it on a
skillet sucks unless its a skillet steak (super thin) in which case a
broiler isn't recommended.
if you want to make an impressive
meal, make carne asada.  it doesn't require a good steak, which is good
if you don't have one.  marinate it in lime juice, garlic, and salt.
cook some yellow rice and black beans, and slice an avocado.  pour a
little lime and salt on the avocado.  it looks very visually appealing
and its my favorite meal.
if you haven't picked it out yet, in
my opinion rib eye is the best bang for your buck.  it can be tastier
than fillet mignon, but not as tender.  as with any steak, look for
lots of marbling (thin veins of fat running through the steak)
t-bones
can be cheap and really big (or at least look big).  the cut isn't
important.  its the price and marbling.  just look for the best cut.
my number one rule cooking steak is DO NOT OVERCOOK IT.  I can deal with medium but well done is an affront to any person who legitimately likes steak.
there's my advice.  god i love steak.