Hello i am currently on Snow leopard 10.6.8, many years experienced OSX/unix user and i can help you. PM i posted also some of my magento works. Mamp or Xampp or this kind of kits are piece of cake, i have better suggestion for you. We will install it through the build in OSX apache server with URL rewrites on and everything working 100% pure, so no useless ram+proccess running in the background. please check pm