I have an oil seascape (24 X 30) signed only "BEVERLY" in upper case letters. It has been in our possession so long that I can't remember how we obtained it. It must be at least 30 years old. The frame notes "Number 101". Is there a way to discover the original artist?

I doubt it.

Perhaps an unknown, first name Beverly, amateur.
Perhaps last name Beverly, also amateur.
Perhaps a town Beverly. http://www.beverlyma.gov/
You will need to take it to several art dealers and appraisers. You haven't posted any pictures of the painting, the frame, the backing, anything. Even then it's dubious.

Where is a picture?