Probably Richard McCarren & ( wife's name) d/b/a Pro Racecraft Engineering. He may say that it's not in his name, but that doesn't mean he's telling the truth. If it isn't, that will come out.
So far as delivering the papers, I would file where it occurred (check with the county clerk...if you're cool they will usually give you a guiding hand). Dunno about MI but in Illinois, you have to have a court-certified person deliver the papers, & you give them all the addresses. If the papers can't be delivered, you can't go any farther (but the people are REAL persistent.
) Since you say the official business address is their home, it probably needs to go there.
To me it's unusual that the court will just send it certified mail...what happens if they refuse delivery, or if a signature isn't required, just act as if they didn't receive it?
Keep in mind also that even if you win judgment, you still have to collect...and therein lies the problem. Here, at least, it generally takes a lawyer to go through the process of garnishing wages...an individual could theoretically do it, but it's not as simple as the small claims process.