Finally got the client working. I disconnected my ethernet and turned on the wifi on my macbook and then the client instantly began updating. That is very strange (wireless works, but wired does not).
I have since ran in to another problem. Now it may be my hardware that's the problem, but I am having insane fps issues at all quality options in-game. For example, if vsync is turned off and all quality settings are set to low, I have a max of 15-30 fps. But, if everything is set to the max, I only get a max of 15-20 fps. Regardless of settings, I am stable at 20 fps.
To give the benefit of the doubt, I am running on a 2009 macbook pro. It has a Core 2 Duo, 4GB of DDR3, and a Nvidia HD Graphics card (not the GT or GTX series, just standard). To play leave over the past 2 years, I've dual-booted Windows 7 and was stable at 60-80 fps until the Rengar patch where is was cut in half to a stable 30-40 fps. Could my hardware be the culprit here? I assumed running it native on mac would forgive some of the old hardware issues 