TI LaunchPad Development Kit is the quick, low cost introduction to TI MCUs. Lots to choose from.
http://www.ti.com/tools-software/launchpads/launchpads.html
I suggest you start with MSP-EXP430G2. The target MCU is MSP430G2553 available in 20-pin DIP and runs on 3.3V.
http://www.ti.com/tool/MSP-EXP430G2
If you want to use Code Composer Studio on a Mac they suggest other LaunchPads.
I found the Development board very interesting. The issue I've got to understand better regards Mac OS restrictions (http://processors.wiki.ti.com/index.php/Download_CCS). I'll try to check it.
Thank you very much.
Regards...