I don't know -- we're in the same boat with the new roof we put up a couple months ago. We have all the receipts.
One thing to keep in mind is that only the *materials* get a 30% tax credit up to $1500; the labor does not. So if a job costs $5000 and $2000 of it was labor, the tax credit would be 30% of the $3000 for materials, or $900. (A non-issue in your case if you are DIYing.)
Beyond that, I don't much know -- it's going to be claimed on your tax return on IRS Form 5695, which is not finalized last I looked. And I don't see any income restrictions listed. You need to keep the receipts and such for your records in case of audit but they won't have to be included with the tax return.
Here's a link to more details:
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