I just used stickie notes on my desktop Mac and I don't know where it went or how I can find it.

Assuming you are using a relatively recent version of OS X, click the folder Applications in the Dock, then look in the window that opens for an item named Stickies. Click it. Your stickie note should then be available.

Hello, please help me with this: I just found the Stickies widget in Dashboard, I created one, but I don't know how to get it to my desktop. When I click outside the dashboard, I couldn't find the note as well. What should I do?

If you want it on your Desktop, copy and paste it to the Stickies application in the Applications folder.