My husband is an independent contractor so he always files his tax return based on 1099 income. This year one of the employers over-reported income by $10,000.00
We have all pay-stubs (with paid year-to-date amounts) to prove that that this 1099 is incorrect. It looks like the employer is trying to pass his tax liability onto someone else. What to do in such a situation? Especially if he is uncommunicative and unwilling to correct the 1099 form?

I would greatly appreciate any advice.

Best option is to sort this our with the employer. May be they have shown some expenses related to your job as your income.
Then call IRS and find out what you should do.

Thank you. That is probably the best course of action.

I also found these instructions on the IRS website:

"If you do not receive your Form W-2 or Form 1099-R by January 31st , or your information is incorrect, contact your employer/payer.

If you do not receive the missing or corrected form by February 14th from your employer/payer, you may call the IRS at 1-800-829-1040 for assistance. You must provide your name, address (including zip code), phone number, Social Security Number, dates of employment, your employer/payer's name, address (including zip code), and phone number. The IRS will contact the employer/payer for you and request the missing form. IRS will also send you a Form 4852 (PDF), Substitute for Form W-2 or Form 1099-R.

If you do not receive the missing form in sufficient time to file your tax return timely, you may use the Form 4852. If you receive the missing or corrected Form W-2 or Form 1099 after you file your return and a correction is needed, use Form 1040X (PDF), Amended U.S. Individual Income Tax Return. For additional information on filing an amended return, refer to Topic 308, Amended Returns. "

The quoted text is copied verbatim from http://www.irs.gov/taxtopics/tc154.html

Normally, IRS will like you to report full amount as reported on 1099-misc. If at a later stage you are able to solve this, you can file amended tax return and claim the refund.