My recent experience suits this requirement, where I developed a full interface between a Wordpress website and a backend database using PhP, JSON, Java with a field on the Wordpress website to enter the name, and then returning the associated detail from the database for that contact.

My assumptions for this quote: This is a Wordpess page, already built, and needing the 'unique identifier number' field A version of the Excel spreadsheet can be made available to me for development and testing Only Microsoft Excel is used The captured client details will be stored in a website forms database such as 'Gravity Forms' and no additional development is required The search return can be on a page identical to the original, but including all the new fields for client details entry, and a 'submit' button All my work can be done remotely. Integration to the living website will be completed by others with me assisting remotely The version of PhP can operate with PhP libraries required for the purpose The Excel file is a .xlsx format and is available to the website for access