Radagast, Pallando, and Alatar

[Pippin]

Gandalf also mentions him to Beorn in the Hobbit.

"I am a wizard," continued Gandalf. "I have heard of you, if you have not heard of me; but perhaps you have heard of my good cousin Radagast who lives near the southern borders of Mirkwood?"
"Yes; not a bad fellow as wizards go, I believe. I used to see him now and again," said Beorn.