If you are interested in the data submitted, you can choose to export the submitted data into arbitrary formats. By default, you can choose from cvs and html if you select the “Powermail-Module” in the left navigation and browse to a page in the content tree that contains your form submission records.
While excel is one of the most established formats to share structured data, their is an option to export the data directly into the microsoft excel (.xls) format. However, this is not available by default, and even if it is documented in the powermail manual, their is no explicit warning or information given by the extension in the Typo3 backend. As a result, you can find many entries in online bulletin boards where people ask how to activate the excel export for powermail.

So to active the excel export icon for powermail, the only thing to do is to install the Typo3 extension phpexcel_library (http://typo3.org/extensions/repository/view/phpexcel_library/current/) which provides php libraries to generate excel files. If this is installed, powermail will automatically recognize it and provide you the export icon in the powermail module.

Note: I have noticed problems to download the excel file with google chrome. So if you are working with chrome and a click on the excel / .xls icon does not result in a download, you should test if the download does work in another browser.

While this sounds a pretty basic requirement, you need to combine multiple concepts to make this happen.
First: To enable permenantly available customizations, you need to use an Add-In.
Second: To extend the menu bar (the ribbons), you have to use makros.
In this post, I will describe those two steps in detail. The post is based on Office 2010 but you should be able to reproduce this with 2007 as well.

Creating an Add-In
To create a custom Add-In, you should create a new workbook (a new Excel file). Next, we need to develop the functionality we would like to provide.

You can do this by either recording a new Makro.
or by programming one using the Visual Basic Editor. For the latter, open the Visual Basic Editor (Strg+F11) and add a new module to your current excel workbook.

Note: It is important to add a new Marko (using a Sub definition in the Visual Basic Editor) and not to programm a new Function because only makros can be added later on to the tol bar. This is part of the second Excel concept you need to understand to extend your tool bar with custom functionality.

When you have finished your Excel makro, you can stop recording or close the Visual Basic Editor and save your Excel workbook as an Excel add in. To this, choose “Save as” from you file menu and select the file type xlam (xla in Excel version before 2010).
Excel uses the common Add-In directory by default. It is recommended to use this directory. Otherwise you need to configure Excel to load your new Add-In from the other directory. You need to restart Excel to force it to load the new Add-In.

As soon as your new Add-In is created, you can activate it in your Excel. To do so, go to File->Options->Add-Ins to open the Excel-Options dialog box.
At the bottom of this box, select Manage: “Excel-Add-Ins” and click on Go to…
A new dialog opens which allows you to activate and deactivate your Excel Add-Ins.
In this dialog, activate your new Add-In and click ok.
By this, your Add-In is permanently available in your Excel and you can use as much as you like to.

Adding Makro Functionality to your Excel Tool Bar

To manage and customize your tool bar, make a right click on your tool bar and choose to configure the tool bar.
In the new dialog, you can configure a new menu group and menu item for your custom makro. To do this, you need to select makros in the select box above the list of the available instruction.
Finally, when you have added your custom tool a menu group on the right, you can select it and click on the rename button to provide a different name and select an icon.

When you have finished all of these steps, you should see your custom feature in your Excel tool bar.

However, the out-of-the-box styles for bibliography lists and especially for the links within the document that link to the bibliography index are very limited in the office distribution.
To adress this problem, the BibWord project has developed a full package of bibliography styles for Microsoft Word.
The project provides a free package available on it’s website: http://bibword.codeplex.com/wikipage?title=Styles
This page includes a link for the download as well as an installation instruction.
It’s simply like extracting the zip archive into a bibliography/style/ directory of your word installation. After a restart of Microsoft Word you are able to use the new bibliography styles.