One big problem with the lawsuit idea. If it's a huge world wide corporation (it is btw) that deals in a specific set of products they have a fleet of lawyers to deal with this. It would be removed from small claims the minute it hit the court room and put right into superior court where attorneys would battle for years and years.
Secondly, your name would most likely be ruined in that industry so good luck getting a job above janitor.
Some times the best course of action is to move on, realize that large companies have no soul or scruples when it comes to employees. I would send a letter to H.R. explaining what transpired and point out that they "should" reimburse me for reasonable expenses due to their bad move.
I would then find an acceptable job for another company since I've retained a good reputation.