Blake White’s books have been useful to many of us in their clear presentation of the gospel and of the doctrines of New Covenant Theology. A list, along with links to purchase them, may be found here.
Cross to Crown Ministries offers video-based teaching series, podcasts, articles, and book resources from a New Covenant standpoint, including a link to resources from John Reisinger. Their recommended reading list/book store is also worth a look.
In-Depth Studies has a great variety of resources on New Covenant Theology and Bible teaching, including articles, book reviews, interviews, study notes, and lessons in audio and video formats.
Sunday School studies and materials (in progress)