Update README.md

Added links for tutorials and documentation

Author: EszopiCoder

README.md

@@ -7,7 +7,8 @@ Microsoft Excel 2010+ (OS must be able to support regular expression object)
 1. Download 'Regular Expression Add-In 1.1.xlam'
 2. Follow these [instructions](https://support.office.com/en-us/article/add-or-remove-add-ins-in-excel-0af570c4-5cf3-4fa9-9b88-403625a0b460) from Microsoft
 ## Usage
-The functions are located under the 'Formulas' tab under the 'Function Library' group in the 'Text' category (see images).
+- The functions are located under the 'Formulas' tab under the 'Function Library' group in the 'Text' category (see images).
+- Please use the following links for [tutorials](https://www.regular-expressions.info/tutorial.html) and [documentation](https://www.regular-expressions.info/vbscript.html) on regular expressions
 
 | Function Name | Documentation |
 | --- | --- |