Normalization rules in Lync use .Net regular expressions (regex) to specify how phone numbers in various formats are matched to patterns and translated to the E.164 format ( http://technet.microsoft.com/en-us/library/gg399071.aspx).

The Lync Server Control Panel provides a normalization rule builder, which helps walk through the process of creating basic regular expressions covering most scenarios. The normalization rule builder’s wizard lets you specify the pattern to match (starting digits/length) and translation rule (remove and/or add digits).

The builder is not meant for advanced regular expressions and the wizard is disabled once advanced items are added to the pattern to match.

Thanks to my colleague Dan Berry which pointed me to Expresso: http://www.ultrapico.com/expresso.htm
Expresso is a free download tool for building and testing regular expressions, it does require registration (free registration code) after 60 days.

Expresso Features:

• Analyzes and describes your regular expression in a tree structure
• Display all matches in a tree structure, showing captured groups, and all captures within a group
• Build complex regular expressions by selecting components from a palette
• Test expressions against real or sample input data
• Maintain and expand a library of frequently used regular expressions

Also located on the site is additional Regular Expressions Resources: http://www.ultrapico.com/Resources.htm