Char, hey there, whazzup?
The quick answer to your question is "no" -- there isn't a method of adding custom-created artwork to the library of existing clipart (teddy bear icon).
It's a good suggestion for the software engineers, however.
Yeah, I can see how that feature would be useful.
As a workaround, just save your logo clipart in .eps format into a unique folder on your hard drive, and then IMPORT whenever you require it in a design.