Sounds like you need a table called tblCompany, with an Identifier column (A, B, etc...) and all other info like Name, Address, etc... Then you would make a query that joins your first table to tblCompany, on the Identifier column. Your report would be based off that query, where you could pull in the Name from tblCompany, and all the other info from the first table.
Unless there's something I'm not understanding?