The following link contains the source code of the R*-tree which we used for the experiments of our SIGMOD'90 paper. The file has to be unpacked with gunzip and tar.
The revised R*-tree (RR*-tree) presented at SIGMOD'2009 is the new version of the R*-tree. The following links provide the binaries of the two implementations for Linux and Solaris. The file has to be unpacked with gunzip and tar.