In 2008, Colin Smith posted a 13-part series as an introduction to textual criticism. I thought that this would be an ideal time to create a post with links to all of those in the series. Hopefully this is edifying and helpful to you!
Alpha and Omega Ministries is a Christian apologetics organization based in Phoenix, Arizona. James White, director, is a professor, having taught Greek, Systematic Theology, and various topics in the field of apologetics for numerous schools.