Were there...
 

any Gods or Goddesses in Middle Earth?

Read ye The Silmarillion!

There are the Ainur who were the offspring of the thought of Iluvatar, the One. The Ainur were mighty in power of song, and mightiest were the Valar, and mightiest of the Valar was Melkor. The Valar came to Middle Earth and did this and that with the elves etc... There is a line in the Silmarillion that says something like:

There were male and female among them. So, if people were going to call them gods, then the females would presumably be the goddesses.

Look ye here. It will answer some of your questions...