Need an email address of someone?
There's a bunch of good ways to find email addresses.
Business email addresses are easy, personal email addresses are more difficult.
To find business email addresses, you can just try the following variations:
[firstname]@domain.com
[fistname].[lastname]@domain.com
[f][lastname]@domain.com
To find personal email addresses, you can try the following as well:
[firstname].[lastname]@gmail.com (or without the dot, it's the same)
[twitter-username]@gmail.com
[linkedin-handle]@gmail.com
Alternatively, or for larger batches, you can use a service that finds it for you:
etc. (there are tons of similar services)
You can also always check an email address for free with Email Checker.