Domain name registered

I had planned to get my first batch of business cards done this week but decided to hold off. Reason being that I found that someone is already using the business name I want to use and the domain name I want to use.

I selected another domain name that I will use instead, and got it registered. I'm thinking about whether I should get my business name registered or not before getting my first batch of business cards done. I learned in class today that registering a business name does not actually protect my business name, it merely identifies me as being the person associated with that name.

So should I register my business name or not? I'll have to register it eventually anyway, so the question really is, how important is it that I register the name before I start printing and handing out my business cards?