If I’m facing felonly domestic and for the third time heading to the pen, can I get a sentence reduction by working as a informant or by turning in a large drug ring?

Hello. The question you ask is not uncommon. In a situation as you describe, I definitely recommend that you privately and immediately confer with an attorney about your interest in making a 'plea deal' and possibly becoming an informant.  Plea bargains may result in you facing lesser charges, or a lesser sentence, or a combination of both.  What you are proposing involves serious considerations of many sorts and, in my view, you definitely want and need attorney help and assistance. I recommend you phone several attorneys in choosing because it is critically important that you feel a sense of great trust with the attorney.  I recommend you choose an attorney who is experienced, and 'seasoned' attorney, and who is familiar with drug culture and related issues.  It is important that you expect to make a few phone calls, because it is very important that you feel great trust with the attorney you select to help you.  Know that attorneys may help you in a limited scope manner, for instance, privately confer with you initially, and this approach can help you discern the best path for you (and your loved ones).  All the best.