I noticed my domain was listed on the blacklist site, Fabelsources. According to the first paragraph of the information I looked up, it said:
Someone or something on your network sent spam to the spamsources.fabel.dk nds blacklist. Some networks (in particular in South America and Asia) don't maintain good records in whois, so a very large netblock including your IP might have been included in this list.
Would it make sense that if I moved my domain to a new host, my IP would change and then I could try manually delisting, since it says I can submit a manual delisting request.
I'm assuming that my IP was somehow included in a block of IP's as it suggested could happen. So if I move my site to a new domain host, my IP address would change. Then submitting a manual delisting request would be the next step since it probably won't get relisted again if it's due to some other IP that is in close proximity to mine.
Just in case it matters: No, I haven't sent spam from my site, not even email newsletters. I've practically never used email from that account except to verify opening some accounts.