The IFS Institute site has all things IFS! Here is the link: https://ifs-institute.com/
Many links to IFS podcasts are available here: https://ifs-institute.com/resources/podcasts-and-teleconferences
You can read articles about IFS here: https://ifs-institute.com/resources/articles
At the IFS Institute site, you also can find contact information for a trained IFS therapist or practitioner, learn about what is required for IFS Certification, see where IFS trainings and conferences are being held, and you can find books and resources in the IFS store. (Often the books in the IFS store are less expensive than other places online, so it is worth comparing!)
Research into IFS is ongoing. If you want to read the original research study showing evidence for the effectiveness of IFS, the link is on the IFS site Resources and is also here: https://www.jrheum.org/content/jrheum/early/2013/08/10/jrheum.121465.full.pdf