Create Reports from CSV

We sell a subscription product but due to our product options (monthly, every two months, cancellations, etc), we're unsure who should get our product each month now that our subscriber base has grown and it is too time consuming and open to error by manually going through the list of customers. Upon the new month starting, we have a CSV of our customers, the product that they have purchased, and relevant information. What we need is a way to pull pre-defined reports from this information to determine who is due to get the product this month, and their details from the report. The report would be: Small Product Customer Large ProductCustomer Small Product Customer - Custom Large Product Customer - Custom Rules, for example: Some customers are active, and are due the product. Some customers are active, but get the product every two months, and received the product last month, therefore they do not get the product this month. If they did not receive the product last month, they would get it this month. Some customers have purchased in the last month, and cancelled, therefore they would be due the product. Etc. What we need to do is have a report created, somehow, perhaps using Excel, or a PHP script that can be run against the CSV, to extract the relevant customers who are due the product, and who aren't, as per the rules and the relevant four reports. We would run the script/report, against the csv, monthly, to make our 'run sheet' for the product dispatch. I can provide a sample of data, and a sample of the rules that need to be run against the data. I have some knowledge of coding, so could tweak rules if need be, I just need the basics in place.