Connecting to Excel Data

Does anyone know (with simple instructions at detail level) how to configure
the DataBase Explorer and its objects to get access (using Delphi tables,
datasource etc) to an Excel workshet configured as a data table (ie columns as
fields, rows as records).

I have set up what I think is some sort of alias which appears in the drop-down
list of Database property of a table, but when I click on the TableName
property to enter or select it, then I get a user entry form asking for a
UserName and a Password. Where should these be nominated, and does one have to
have them ?

Thanks in anticipation.

Alan Lloyd