The FRS Individual Income Series is derived from the FRS and the HBAI (which is also derived from the FRS). Questionnaires are included in the FRS online documentation and are also available at from the Survey Question Bank: FRS Questionnaires.
ESDS is now part of the UK Data Service.
These ESDS web pages will remain during the transition, but may not be up to date.
Here are some links to get started with the new service:
Statistics web 2.0