Spam Comment On Unfinished WordPress

I've been working on one of my niche blogs and haven't got it fully up,just a default wordpress template and i got a notification that someone posted a Comment on the wordpress blog,it's an attempt to get a back link for a tread mill niche(odd considering my website is about a completely unrelated niche),the site is using amazon affiliates for income
The comment came from an xsserver VPS

Wondering who it was and how they found the website
the only people who knew the site even existed were:
-The person i bought the EMD from
-A person on here that was writing free articles
-A Person doing SEO on fiverr

But i'm thinking they used some sort of scraper to find it,though it's not even ranked

Any ideas on how they found the site & prevention of more comments?

They scraped a list of blogs to send automated spam to. Scrapebox most likely. A quick fix is to go into the admin panel and turn off comments.

if Google can find your site
then a spammer can also query for it

google for: ""Edit or delete it, then start blogging""