Are these the two things I need? (I'm on monoprice)
Mini DisplayPort | Thunderbolt to HDMI® Adapter w/ Audio Support
3ft Premium 3.5mm Stereo Male to 3.5mm Stereo Male 22AWG Cable (Gold Plated) - Black
That looks like just what you need. A Mini DVI to HDMI adapter. Even if it says its ready for audio, you still need the other audio cable as the MacBook won't support audio out through the Mini DVI.
from Common video interfaces on Macs and the appropriate adapters to connect to other display devices