Hey,
Not sure about software. I read a quite interesting article about 'the domain drop' process last year (afraid I can't remember the title).
Big companies offer web based services for people to catch domains that are about to drop - its like a big fight with first request winning.
Heres one article:
http://www.sitepoint.com/article/name-goldrush-1-rules-play
Lots more on google. I would definately say paying for one of the companies to try and catch the domain is the way to go.