Nancy,
We might be talking about different things.
(1) Under the FLEX 2.0 examples, you could, for example, go to the
FLEX Style Explorer,
http://www.adobe.com/devnet/flex/samples/style_explorer/
(2) Then click on "Experience the application" which leads you to here,
http://examples.adobe.com/flex2/consulting/styleexplorer/Flex2StyleExplorer.html
(3) You can then Right Click anywhere on the app and click "View
Source" and it appears for the MXML page, and then to the left you see
all the files for actionscript, components, etc. And There is a
download source (ZIP) link at the bottom.
Does any of this appear for you for the FLEX 3.0 component explorer
below,
http://examples.adobe.com/flex3/componentexplorer/explorer.html
Or for any other FLEX 3.0 example for that matter?
Hopefully they will be updated soon.
-r