IRS Publication 938 Real Estate Mortgage Investment Conduits (REMICs) Reporting Information has information regarding reporting REMICs. You can use the directory in the publication to find the representative of the REMIC, then request information from that representative by telephone or mail. Your request must specify the calendar quarters and the classes of REMIC regular interests for which you need information.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the webpage or document at the time it is accessed.