I filed my taxes and the IRS has rejected them. We believe that it is because my husbands employer did not file or pay the employee taxes that were deducted from the checks. What and who should we contact?

Your employer is the first people, and see if they did pay their share of the SS taxes, and also all of the taxes they withheld from your check.

After that the labor department, and a personal attorney

Agreed. Failure on the part of the employer to file Form 941 and pay these taxes is a VERY serious offense with both the IRS and the state tax authorities.