If you have not logged in before then you may still need to verfiy your account email address. You can do so by clicking the verification link in the email that was sent at the time your account was created.
To log in as an event organizer you can start at https://app.geotix.com/login. Note the "s" in the "https" at the start, this means the the login is from a secure site (see #1 in the image below). You may also be able to access the log in from https://secure.geotix.com/login. From either page, you will be prompted to enter your account email address (2) and your password (3). Then select Log In (4).
If you forgot or never have set your password, then enter your email (2) and select "Forgot Password?" (5). You should see a notice at the bottom of the screen that there was an "Email sent" to your address with instructions to reset your password.