You can't use the formula bar to change text case for a range of cells.
You will need to use a macro instead.
Here is an example on how to use the formula bar to add a new column with the formatted text: http://www.youtube.com/watch?v=KPpFSjarX9I
What is a macro?
A maro is a series of commands that are automated with a scripting language.
The text that you want to change, is it confined to a single column or row?
Where are they automated with a scrip language?
Macros are ran under the View ribbon, but I think your best solution will be to use the example provided in the above video.
It will allow you to create a new column with the correctly cased text that you can then copy and paste over the old column.
OK I will check thanks!