Mail merge sounds like the Word 'function' you need.
It allows you to setup a document using named fields, and these named fields are drawn from a data source, such as Excel.
If your Excel worksheet has a series of 'fields' i.e. columns containing:
Select the range of cells containing your address data including a headings row as suggested above.
In the address box in Excel - the area just above the column letter A and the Row number 1, which displays the active cell address, type in a name for the table, e.g. Wedding Addresses. Click OK (you must click OK with the cursor still in the address box). Save the Excel file.
In Word use Help to find the Mail Merge Menu/ Mail Merge Helper (I don't have Word 2007 on this PC, so I can't give you the steps) and use the Mail Merge Helper to step you through the process.
It will allow you to link directly to the range you named ("Wedding Addresses") in your Excel Workbook and to map Word's address fields to your headings, and then print a series of envelopes.