someone sent me an email, and said I was a googlewhack.  They didn't say which site or why though.

A googlewhack, is making a phrase (usually a question) that the google site points out the answer to.  So if you put "miserable failure" into google, the GW Bush bio on the White House web page comes up.  This is because a bunch of people used the phrase "miserable failure" as a link to that page.

There are several sites that list current googlewhacks, do a google search for them.

Chucky

A googlewhack is a unique hit with a two word search on Google, i.e. Google returns one site and one site only as a result of that search. The search words have to be real words checked against the Oxford English Dictionary. People play this game and register their googlewhacks on one the "whack stack" at of the sites dedicated to the pastime e.g. www.googlewhack.com

It's getting harder to find new googlewhacks as time goes on and people register their finds. The email you got was probably from someone who'd located a googlewhack on this site - did it say what the search words used were?

There's a British comedian called Dave Gorman who's popularised googlewhacking in the UK. He's doing a UK tour at the moment talking about his "Googlewhack adventure", where he finds a whack then goes and visits the person who's site he found it on, be they in the USA, Australia, wherever...
then asks them to find their own whack which he follows to his next destination.