What's the easiest way to get 32-bit binaries for BLAS and LAPACK on a 64-bit Ubuntu distribution? It seems that there's no lib32blas or lib32lapack library available.
Manually compiling those libraries is the normal method of installation. It is fairly strait forward and you may want to look at ATLAS as it often can provided better performance. By using the -b 32 compile flag you can make sure that a 32 bit library is created.