I disagree. The coasts don't have a monopoly on software engineers for two primary reasons:

1) The midwest/mountain states have lots of great CS programs in their universities. UIUC, Boulder, UT, GA Tech, UW-Madison and plenty of others, as well as a lot of small universities that don't get the attention of Google and Amazon. My alma mater only produces a dozen CS grads a year but some of them have gone on to start insanely successful companies (Rackspace, for one).

2) Lots of great software engineers don't want to live in California, New York or Boston. I grew up in the Bay Area and I have 0 desire to move back. I hated it there and I know I'm not alone in that.

Well, if you're willing to pay for it, you could probably poach engineers by offering better salaries. I've noticed job listings outside of the Chicagoland area that are easily 15-25K less than what I could get in Chicago... and Chicago is low compared to NYC, Boston, SF, etc.