There was a lots of paid and free spam detection tools are available on internet, if you suffer from spamming problem then you make sure choose best and affordable spam protector tool from the web according to your requirements.
If you tweak server settings properly, you can easily trace spammer on the server and suspend it. If cPanel is the control panel, you can enabled extended logs in exim it will help you to detect any script or email account sending the spam.
to protect from the spammer you can use captcha email authentication make sure the website you using does not have any venerability which can be use by spammer . also its depend on the server on which your domain is hosted the server should be secure enough to protect from open relay protect using the antihack / anti spam protection.
The best option is to make sure that the application installed in your website is secured with upto date patches. Your application should have the latest stable version. Remove unwanted plugins and themes from your website.