You can buy plain gift tags at many craft stores. I got the ones for my orange-cranberry granola at Michaels. But, sometimes you may want to kick it up a notch and print out something a little prettier.
If so, you'll love these links.
I'm continually amazed at the talent some people have for creating beautiful, digital art such as these printable gift tags.
Image courtesy Ellinee
Image courtesy Crafts with Jars
Mason Jar Chalkboard Tags @ Crafts with Jars