Three books in particular (and countless journal articles) that made a huge impact on me and continue to rank among the most important in my position as a biblical egalitarian:
1) Paul and Gender: Reclaiming the Apostle’s Vision for Men and Women in Christ by Cynthia Long Westfall. Download/Read an excerpt here. Listen to an interview with Dr. Westfall here.
3) Discovering Biblical Equality: Complementarity Without Hierarchy, (eds) Ronald W. Pierce, Rebecca Merrill Groothuis, Gordon D. Fee