Start searching on this site which gives you access to every property on the market in Massachusetts. There is advanced search criteria allowing you to specify what you want. Once you see you something you like simply request a tour:
Hope that helps! Good luck!
First focus on what area of Massachusettes you would like to purchase in and what price range you are qualified for. Then interview a couple of local realtors who specialize in that area, and choose an agent who you would like to work with to represent you. Sometimes, these realtors have inside knowledge of condos coming on the market before they hit mls. If you would like me to refer a highly qualified agent in your search area, let me know. I'll be glad to help. Good luck in your search!