Affiliate Marketing Secrets

I bought a business just recently, and another person who used to be affiliated with my business decided to start there own exact same one, except they left out one letter… ex.
George’s Online Store(s)
George’s Online Store( )
This person made there own business using all my copyrighted info which i purchased the rights to because the previous owner ran the business poorly.
I purchased it, put a lot of money into it and now im finding out that their using it. Only thing is, I am just filing for a trademark now, but my business has been running since 1990, this other person just started theirs.
I understand I probably have to wait for it to be approved, but is their anything I can do in the mean time. This person is ridiculous, who would be that stupid when they could get sued?!