Civil Rights: Rhetoric or Reality? is a fabulous book, not outdated at all. In fact, I’ve assigned it to my introductory students this semester, as on several previous occasions.
Besides that one, Sowell’s Preferential Policies: An International Perspective also obliterates the argument — I should say “assertion” — that discrimination accounts for differences in group achievement. That one is a bit dated, but still characterized by the author’s trademark cogency.