Hi Daniel,
Finding a shortcut in help is not very simple, because they are
split up into categories with separate help panels and that does
not help you. I have placed the Excel keyboard shortcuts onto
a webpage with the same information extracted from HELP so
that you can use FIND within your browser.
Shortcut Keys in Excel 2000 (Excel Vers. 9)
http://www.mvps.org/dmcritchie/excel/shortx2k.htm
The shortcut key you were looking for is in the category
Keys for editing data
Another hint:
Microsoft lists such shortcuts in their products as
"keyboard shortcuts" so look for keyboard in HELP
and Microsoft is very lax on including mouse shortcuts at all
so you might also take a look at.
Use of Mouse and keys to move, and insert rows or columns
http://www.mvps.org/dmcritchie/excel/fillhand.htm#mouse
Thanks for telling us you looked in HELP first.
You can also access this through the menus.
Alt+I (Insert), Enter because Cells is highlighted