The original multi-part standard, ISO/IEC 29500-1:2008, ISO/IEC 29500-2:2008, ISO/IEC 29500-3:2008, and ISO/IEC 29500-4:2008, is freely available at http://standards.iso.org/ittf/PubliclyAvailableStandards/index.html.
The first set of technical corrigenda to the original, ISO/IEC 29500-1:2008/Cor 1:2010, ISO/IEC 29500-2:2008/Cor 1:2010, ISO/IEC 29500-3:2008/Cor 1:2010, and ISO/IEC 29500-4:2008/Cor 1:2010, are freely available at ISO Store.
The first set of amendments to the original multi-part standard, ISO/IEC 29500-1:2008/Amd 1:2010 and ISO/IEC 29500-4:2008/Amd 1:2010, are freely available at http://standards.iso.org/ittf/PubliclyAvailableStandards/index.html.
Two corrigenda to ISO/IEC 29500-1:2008/Amd 1:2010 and ISO/IEC 29500-4:2008/Amd 1:2010 have been approved but they will not be published. The content will appear in the second edition (see below).
The second edition, ISO/IEC 29500-1:2011, ISO/IEC 29500-2:2011, ISO/IEC 29500-3:2011, and ISO/IEC 29500-4:2011, has been created by merging the original, corrigenda, amendments, and corrigenda to amendments. It will soon be published and become freely available at http://standards.iso.org/ittf/PubliclyAvailableStandards/index.html.
To address issues around the use of ISO 8601 lexical date formats for spreadsheet cell values, WG4 has started projects for creating the first set of amendments to ISO/IEC 29500-1:2011 and ISO/IEC 29500-4:2011. Draft amendments have been created and will soon be sent out for five-month combined ballot by ISO and IEC.