Welp, thanks to the "webalizer" provided by my site host, I found a reference to Adsoft Development. Since there are NO ads on my site, I looked them up. Apparently the guy who runs this site is a known guestbook and forum spammer (and now blog spammer, I imagine). Here is Spamhuntress's page on him. If you look at the domains used by adsoft, you will see that some of those listed are used in the spam comments that come up when I do a search.
I asked my site host about this and they said that could block certain IPs and domains from my site. They directed me to CPanel's "CPanel / IP Deny Manager" where I can block IPs, and for changing the .htaccess log directly, THIS SITE.
Using the list of domains provided by Spamhuntress, I blocked the domains using the htaccess file.
Akismet is very good about catching comments from this spammer, so I am already protected against any of their spam showing up on MY blog. What I am hoping is that my link will become useless to them (whatever benefit they get from it!) and will stop showing up in their forum spam!
If anyone has any other ideas, let me know!