We do not allow users to post advertisements or commercial solicitations on our forums. This includes touting one's own equipment for sale. Advertisers wishing to take advantage of our site are welcome to contact us for banner ads. However, we do not have a problem with users posting links to their web sites in signatures, or posts provided their posts are materially useful and are not simply seeking to promote their products (e.g. recommending themselves for every query). Generally we are less tolerant of posters who do have commercial signatures when it comes to what is and is not abuse. We are less strict on ISPs posting in their own forums. Note that the restriction on advertising includes linking to schemes where you receive a commission or benefit of some kind from a user signing up.
To add to that this includes pestering people in private message too, so given your public admission means a suspension is the only recourse