email: sra-tools@ncbi.nlm.nih.gov
It has been broken into four separate repositories:
https://github.com/ncbi/ngs.git
https://github.com/ncbi/ncbi-vdb.git
https://github.com/ncbi/sra-tools.git
https://github.com/ncbi/ngs-tools.git
You should clone all four of the repositories above.
SRA Toolkit Development Team