Find and open phpmyadmin and select your database. Find the Tableadmins" and select the action "Browse". There you will find your admin login and password. The password is md5 encrypted, so you cannot just change it to "password". You will need to use an online tool Md5 Creator Online - Crytoplogy to convert a password to md5 format.

For example, the work password in md5 format looks like: 5f4dcc3b5aa765d61d8327deb882cf99

It is a good idea to download and backup your database before attempting this operation.