Help with EXCEL document

I have an EXCEL document with 2 worksheets.  These worksheets contain about 400-500 records each.  The columns headers that makeup these worksheets contain a Name Column, Service Date Column, Drug Information Column, etc.

The two sheets are ALMOST identical in data, including the format.  For example, the Name Column in both sheets is formatted so that the full name of the customer appears, Last Name first.  While the Service Date is slightly different in each worksheet, in that one worksheet displays the date as 11/01/07 while the other worksheet displays the date as 11/01/2007.

It may help to build my business scenario at this point, before I provide the challenge Im running into and the details of the surrounding data.

I have a drugstore running an application.  This application captures 2 sets of data (output in two worksheets) and provides it in an EXCEL workbook.  The first worksheet captures only 1 transaction per customer who picks up and pays for a drug.  This data is fine as long as the customer is seen only once and collects only one drug.  Both worksheets reflect the single transaction.

However, if another customer comes in more than once, say during a three-day period, and collects more than one drug during each visit.  Both worksheets may/may not reflect each visit correctly.  And, the first worksheet ONLY captures the data that only one drug is picked up, while the second worksheet captures all drugs which were picked up.

My challenge is Im trying to reconcile the data between the two worksheets.

This is just me thinking out loud - its definitely not a must have.  My thought is to create a third worksheet, generate some sort of query, filter, macro so that EXCEL will compare the two worksheets, and if it sees a difference in the number of  a Service Date for a customer or the Prescription Number of the customer it will flag it or make a record of it in the third worksheet.

For example, if there is only one record of a transaction (for customer john doe), on MM/DD/YYYY worksheet A, but there are 5 records of the same transaction in worksheet B, output the name in worksheet C.  While, if there is only one record of a transaction (for customer jane doe) in worksheet A, and ONLY one record of the transaction in worksheet B, DONT output the name in worksheet C.

The commonalities between the two worksheets is the Customer Name (including format, for example last name first), Service Date (formatted slightly different, but can easily be changed so that both formats are the same) and Prescription Number.

In the past Ive had to manually reconcile the two worksheets, which took days.  My goal is to automate this process so that its not so labor intensive.

Please keep in mind that this process DOES NOT have to remain in EXCEL Id be more than happy to try to accomplish this via some script through ACCESS or SQL.  I just thought since its already in EXCEL, I might be able to avoid another step in the process.

Thanks.