So I want to send emails containing some information and a link, and I want to know is it possible somehow (in Javascript/PHP...) to get the email adresses of those who accessed my website through that link.
Thank's.
You can expand your link, for example http://mysite[dot]com/email.php?mail=useremail@gmail.com. If user clicks link, you can follow their actions.
If user (with email useremail@....) clicks link, do whatever you want in your email.php file.. Store in database or use Analytics.
PHP
$_SERVER['HTTP_REFERER']
holds the information. In order to have email address, that may be in HTTP_REFERER but i didn't check. You get information if it is from email. Than you can prepare url in email campaign to click, so it holds user email.