(Note: If you want to just skip to the good parts, use this nice document for configuring unixodbc and freetds only: How to Install FreeTDS and UnixODBC on OS X)
This totally sucks, because the MSSQL database connection tools on OS X don't exist. You're going to need to do the following:
brew install unixodbc
brew install freetds --with-unixodbc