RegexBuilder: The first one I'll start with is free and can be downloaded and run without an installation routine. It allows you to type or paste in your expression and test against it on the fly. This tool is great for performing simple validation of an existing string but you really need to know how to write one before you start with this tool. There are no 'helpers' to assist you with wondering the difference between "\d*" and "\d+", which by the way, I still don't know the difference. ;)
Download location: http://renschler.net/RegexBuilder/
Expresso: This has to be my favorite tool thus far. It can be downloaded for free and by simply filling out their online registration form, they will send you a registration code. What I like about this product is that they give you examples and show you what each character means (even though \d* and \d+ are still not clear to me). The GUI interface allows testing of multiple strings and their translations so you could take a copy of your ABS normalization text file and paste it directly into the 'Test Mode' screen to verify your results.
It can be downloaded at: http://www.ultrapico.com/Expresso.htm
RegexBuddy: If you have a few bucks lying around and want to give this application a spin, it certainly does the trick and more. This might be a good place to start for the beginner since the interface is much more helpful than the other two. At $39.95 USD it appears to be a pretty good deal however in the context of doing dial plans for OCS, I'm certain you can get what you need out of the other two combined.
That's all for today.