I was told the same thing by Turbotax (that I was not eligible for a 2007 tax refund, all of my earned income was earned in the UK, and in fact I had to pay the IRS for the past few years, so the IRS has my bank account details on file via EFTPS).
However, the tax year refund and economic stimulus payments are notionally separate.
I received my economic stimulus payment several weeks ago (transferred directly into my bank account) with a follow up letter (yes, by post) explaining the payment to me, etc.