Comment by kcrisman for First, the instructions seem to indicate that if you copy the file sagetex.sty into a directory with your latex file, then the system will be able to find it. Can you first verify that this is the case?After that, can you try putting sagetex.sty in the default search location? On the mac, that's ~/Library/texmf, so I guess you should put sagetex.sty in ~/Library/texmf/tex/generic/sagetex/. Note that a new "feature" in Mac 10.6 makes the Library directory hidden. You can navigate to in with the Terminal, or select it from the Go menu (you have to hold down the Option key to see it).Edit by kcrisman: with the upgrade to SageTeX 3.0, the default location in Sage will in fact be $SAGE_ROOT/local/share/texmf/tex/latex/sagetex/ which should be placed in ~/Library/texmf/tex/latex/sagetex/, I believe.

There are a lot of interesting issues with the `~/Library` directory; see http://www.macworld.com/article/1161156/view_library_folder_in_lion.html and http://www.macworld.com/article/2057221/how-to-view-the-library-folder-in-mavericks.html