OSX 10.8.5, UpTeX installed, (Not sure what else I installed).
Running tlmgr installs package in /usr/local/texlive/2013basic/texmf-dist/tex/latex/biblatex.
Put a symbolic link into /Applications/UpTeX.app/teTeX/share/texmf-dist/tex/latex and run texhash.
$texhash
texhash: Updating /Applications/UpTeX.app/teTeX/share/texmf/ls-R...
texhash: Updating /Applications/UpTeX.app/teTeX/share/texmf-config/ls-R...
texhash: Updating /Applications/UpTeX.app/teTeX/share/texmf-dist/ls-R...
texhash: Updating /Applications/UpTeX.app/teTeX/share/texmf-var/ls-R...
texhash: Updating /Applications/UpTeX.app/texfonts/ls-R...
texhash: Done.
Then I can run the new package with pdflatex.