What to do when you see a black widow

First, run and grab a can of wasp spray because you're too chicken to squish it with a shoe.  Next, nonchalantly walk over and spray that spider for all you've got.  Realize you should have got a shoe while inside.  It's too late now, if you leave the scene of the future crime, your victim will escape into the gravel.  Spray more every time it moves.

Now if you take some time to look around, you may notice a tick or two crawling up a deck post.  Spray them while your there; you've got nothing better to do.  You may even want to sing a happy "die, die, die" song in your head as you imagine them not feeding on your children this summer.

Now back to the monstrous spider.  Try to end the stalemate by calling your neighbor girl over to get you a shoe (note to self: wearing shoes would provide me with better weapon options).  Never get closer than two feet to the spider.  The wasp spray may give him mutant jumping powers.

FACT: 1/2 can of wasp spray will eventually kill a black widow.  EVENTUALLY.  The waiting is hard if you aren't sure of this fact.  It will not happen quickly. The giant spider may still look very healthy, very spry, and very large.  

Do not be intimidated.

If you are intimidated, ask your neighbor's husband to come over and kill it for you.  You are now desperate enough to wait until he gets out of the shower.  (Lots of waiting...remember). 

Feel slightly humiliated when said neighbor grabs a two inch stick to poke it with.  Watch as it falls over with it's limb frozen in space.  It's dead.  Rejoice!  Oops, you may wish you had grabbed a picture of this awesome spider before said neighbor squishes it and throws it into the bushes for you.  

Bake said neighbor cookies anyway, while mourning the lost picture opportunity   Seriously, it was the most perfect specimen I've ever seen.  

Finally, in the good to know department:

How dangerous are black widow spider bites?
If a black widow spider bites a person, do not panic! No one in the United States has died from a black widow spider bite in over 10 years. Very often the black widow will not inject any venom into the bite and no serious symptoms develop. Wash the wound well with soap and water to help prevent infection.

If muscle cramps develop, take the patient to the nearest hospital. Some victims, especially young children, may be admitted overnight for observation and treatment. There is treatment for a black widow spider bite that can take care of the symptoms. Various medications are used to treat the muscle cramps, spasms and pain of a bite. Black widow spider antivenin is seldom necessary. 
http://sta.uwi.edu/pic/bitesAndStings04.asp