I officially registered and copyrighted the name of my event planning business. It's called Bliss Events. I have to register a domain name (website address) for my business, but all the ones I have checked have been taken (i.e., blissevents.com, bliss.com). I don't want to use any other extensions than .com. Anyone have any suggestions for a dot-com website name for my business?

Since the domain name you wish is taken, try incorporating what your business is with the business name. In your case your providing a service to others for their events. My suggestion is "yourblissevents.com" At the time of this answer the domain name was available.

I like the previous suggestion.

Here's another blissevents4u.com or blisseventsforyou.com (although the latter is quite long.)