That depends on your intent. Do you want the mere appearance of a check box, or are you designing a PDF form which will include a live, interactive check box?
If it's just the appearance, many dingbat fonts include glyphs for representing things like check boxes, or you can use the drawing tools in InDesign or another application to create a graphic depicting a square and check mark.
If you need a live, interactive check box, and you're running InDesign CS6 or later, you can add a check box to your document by using the rectangle tool to draw a square, then click the Convert to Button button at the bottom of the Buttons and Forms panel (Window > Interactive > Buttons and Forms). Then choose Check Box from the Type: menu at the top of the Buttons and Forms panel, to enable the other Check Box options.
Ariel, your posts are coming in blank....
Thanks Peter (when is Jive going to be able to cope with HTML emails???
It's 2014 already). I was going to say (but John gave a more complete
Just find a checkbox glyph in a font that has one -- worth looking in
various pi fonts. Adobe Pi Std has one, for instance.