Helping people with computers... one answer at a time.
It's difficult to find the email address of someone you want to contact. In order to find the email address, they must want to be found.
How do I find out my friend's email address?
I'd like to get in touch with my old college roommate - how do I find out her email address?
I'm trying to get in touch with a business contact, but I've lost his email address. How can I find it again?
As you can tell, I get variations of this question a lot. In short, you know someone, you want to send them email, but you don't have their email address.
What do you do?
Well, I'll be blunt. Nine times out of ten, you are simply out of luck.
But sometimes you can get lucky.
Again, I'll be blunt. Finding someone's email address is typically very, very hard. Nearly impossible in the general case. There are several reasons:
There's no central database or "phone book" for the internet. An exhaustive search could have you looking in tens or hundreds of different resources.
The planet is bigger than you think it is. If all you have is a name - any name - that's not enough. There could be many - perhaps thousands - of people with the same name. In most cases you'll need more than just a name.
Not everyone wants to be found. It's easy to set up a free email account with information that has nothing to do with who you really are. So even if you know a lot about the person you're trying to find, they still may not be findable.
Not everyone has email. Heresy, I know, but the fact is many people you might be looking for are not on the internet at all.
So what's worth trying?
My first reaction is almost always Google. For many people, Google might take you straight to them. For example at this writing, searching for me, Leo Notenboom, will get you 6 pages of results that are all right on target. Unless you're looking for a different Leo Notenboom (I know of at at least two others), in which case you'll need to do more work.
Now, obviously, I have a relatively unique name, and a very big "footprint" on the internet. If you're looking for something more common - say "John Smith", you have a lot of work ahead of you. You'll need much more information to narrow down your search to exactly which John Smith you're trying to locate. You could include anything from the city he lives in, the place he works, the school he went to ... anything that might help narrow down the search. But even then, you're unlikely to get the right person, unless they really have an internet presence, and your information really matches well.
I have a case where I occasionally look for my former roommate, as well as the best man at my wedding, both of whom I've lost contact with over the years. Their names are somewhere in the middle - not as unique as mine, but certainly not as generic as "John Smith". I have yet to find them. I keep finding people with the same names in other places that are obviously not them.
If they want to be found, and you suspect that they have accounts with services like MSN, HotMail, Yahoo or others, it might be worth checking the member directories within those services. If their place of business has a directory, that might be worth a look. Similarly, if you have reason to believe that your contact might have joined any of the social networking sites such as Linked In, Orkut or others, you might check there as well.
What's important to note, though, is that for member directories to work, the person must want to be found. Even if they have an account, they may elect to keep their information obfuscated or private, and searching the directory will do you no good.
You can always try the phone book. All of the major phone companies have on-line phone books that include both the traditional white and yellow pages. You may not get an email address, but you may be able to locate your contact in the "real world". Once again, if they've elected to have an unlisted number, or they do not have a telephone of their own, you may be out of luck here as well.
And finally, there are for-pay services that claim to be able to find out all sorts of information about people, mostly culled from public records also accessible elsewhere. I've never used one, and cannot recommend any specifically.
So in a nutshell, I'll reiterate - most frequently it's practically impossible to locate someone's email address. You can get lucky, but it's rare, and can often require a fair amount of effort and legwork.
Important: do not post comments to this article of the form "I'm looking for some name's email address, please help me." Please read the article above. Posting people's names and personal information here will not help, and is, in fact, violating the privacy of the person you are trying to locate.