Start slow. Run in place in your living room for five minutes a day. That'll get striking on your mid-foot. There are lots of good resources out there, among them barefootrunninguniversity.com (that's Jason Robillard's site, where you can download a PDF of his very good book for free). There is a two-part blog post on http://runbarefooteurope.blogspot.com
(Teach your Boss to Run Barefoot parts 1 and 2) that sums up some of the most important points that it's taken me eight months to come to realize on my own (cadence being the most important).
I want to start- I have flat feet and barefoot is supposed to help