I invested 30 thousand dollars into a friend's business two years ago. I have yet to receive any type of reimburstment. How do I get my money back

The answer to your question is that you should review whether or not you have any form of Agreement with your friend for the terms of the investment.  Was the money an investment or a loan?  Did you obtain any equity in the business?   You should have Counsel review the terms of the transaction with the understanding that you may need to sue your friend.