Do you mean ADODB recordsets, or a data set? If you mean ADODB
recordsets, then you can use COM interop and use the JET OLE DB Provider to
get a recordset in C#.
If you mean a DataSet, then you will have to use COM automation to
access Excel, and get the information programatically to populate the
DataSet.
The Knowledge base article 316126, titled "HOW TO: Use Visual C# .NET to
Automate a Running Instance of an Office Program" should help, it is located
at (watch for line wrap):