I now have the MP3 player hooked up to the Netduino and all of the switches appear to be working. The potentiometer was shot and the rest of them did not function much better. I will need to look into getting replacements.
Luckily I was able to find some code on the Netduino forums and the heavy lifting of getting the Netduino to communicate with the VS1053b over SPI was already completed. They are a great resource, check them out if you have any questions.
Code from the Netduino Forum for the VS1053b (Thanks hanzibal!) I made some tweaks to a few areas for it to work in my project. I will put everything in the next and final (for now) post.
Now to try to put everything into the case and make it look better for the living room.