Essential Resources for Locating and Using Numeric Data

Open Refine
A free, open source, powerful tool for working with messy data:  cleaning it; transforming it from one format into another; and extending it with web services and external data.

Regular Expressions
Regular expressions are a concise and flexible tool for describing patterns in strings. These are online tools for experimenting and testing with regex:   https://regexr.com/ and https://regex101.com/.  This is a useful tutorial for historians.