The wife has most of the data in Excel at the moment, so should be able to get quicker results with that. Have got a Excel 2007 book and 2 hours watching the kids swim in a minute to try to puzzle that out.
Access is something I've always wanted to learn, but never had a good enough reason to do it. So now I might! This will be a long term replacement for the quick fix in Excel.
If she has most of it in excel the transferring it to access before you start playing with vlookups might be a better option - if you want me to tell what data should go into what datasets then I'm happy to do this or you can have a go and send over what you think should go where...
The general rule of databases is splitting down grouped data into unique chunks that aren't repeated...
For example your paying members will be be unique and would be assigned a unique ID but they may have multiple family members but each are unique so they would go into a separate table and asigned a unique ID with a reference ID to the unique ID of the paying member (relationship). Likewise their payments would be multiple but unique so again each would have a unique ID and a reference to the paying member ID.
Once you have your database table and datasets you can then start building queries using the relationships (far easier than vlookups!)