Here is how you can get the MSL on a Samsung Epic 4G. This process may work on other phones too.
Install the free Android Terminal Emulator from Google Play.
At the CLI prompt, type "getprop ril.MSL" (no quotes, note the capital letters).
The number returned is the MSL (master subscriber lock) code for that phone. This can be used for advance programming of the phone, such as Ting's upcoming BYOSD.
This process will likely work on other phones. It does not work on my Ting HTC Detail, though.