I find this option useful on Windows, run cmd from the command prompt, then in there just type widget

C:\Documents and settings> widget
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This invokes an application that gives many useful scripts demonstrating what you can do with Tk widgets, it runs the Tk program demonstration for you to watch it with provision for parameters modification and from there you are provided with a button to see the code with regard to the demonstration you ran too.

Now Scroll to the heading Common Dialogs you got links to the following there:

1. Message Boxes.
2. File selection dialog.
3. Directory selection dialog.
4. Color picker.

I don't know if this is available when you're running another OS than Windows but let's hope that this be of some inspirational value to you.

To get a description of what "widget" does check perldoc.

C:\Documents and settings> perldoc widget
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