This is how I did it. Your mileage may vary.
Prerequisites:
- XCode with command line tools
- MacPorts
- cmake, autoconf, automake, libtool, libusb*, rtl-sdr
All programs listed on the last item above came from MacPorts**, with sudo port install PROGRAM with the exception of libusb. The first four on the list are required for compiling the last two from source -- and in that order, because rtl-sdr depends on libusb. Unfortunately, compiling from source did not work for me: rtl-sdr kept failing to find libusb. Installing them from MacPorts did the trick. Upshot: save yourself some trouble, use MacPorts. Other upshot: it's entirely possible that if you get rtl-sdr from MacPorts you don't need any of the first five programs in that list.
* For libusb I did sudo port install libusb +universal because of this thread.
** After you install MacPorts you can check port version but you have to do it in a fresh terminal window. You will find it, then you can do sudo port selfupdate just to get into the habit. Three more things:
1. Every single thing you install with sudo port install will have to be launched from a fresh terminal window.
2. Do sudo port selfupdate often.
3. See also your other sudo port options: clean, uninstall, upgrade.
I think I'm on my way to putting this thing to use. See below:
$ rtl_test -t
Found 1 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001
Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
Sampling at 2048000 S/s.
No E4000 tuner found, aborting.
Alright, I'm sure that this "No E4000 tuner found, aborting." is some cause for concern, but this note is about getting started.