Yup, me too. This is, I think, one of the by-products of the recent glut of worms. Our e-mail addresses and those from our Contacts' address books or other Newsgroups or Bulletin Boards have been spread around the world.
You can use OE "Rules" to some extent to block e-mails from certain addresses or with certains words (viagra?) in the Subject Line.
I personally send all e-mails from a Yahoo address straight to the deleted folder. But I do have a peep before emptying it in case it's from someone I want to hear from!
This curse will go away one day, but until then I'll just give them the same treatment as I give the spam that drops out of my newspaper or magazine or onto my doormat in spite of the notice on the door. Delete before reading!
Guard your mobile 'phone number too; there are some sick people out there!