Hi Woodelf. Here's how to get the icon back:
In Windows 7 (and possibly in Windows 8 too):
Click the Start button, type 'desktop icons' into the search box, and then click 'Show or hide common icons on the desktop'.
In the Desktop Icon Settings dialog box, click to place a tick in the Recycle Bin check box. Click OK.
In Windows Vista:
Go to Start and click on Control Panel. Then click on Appearance and Personalization, followed by Personalization.
In the left pane, click Change desktop icons.
Click to place a tick alongside the Recycle Bin check box.
Click OK.
The Recycle Bin shouldn't disappear to option to hide it), so I'm hoping that's not what you're using!