I have written an undergraduate textbook entitled Algebraic Combinatorics: Walks, Trees, Tableaux, and More, published by Springer in June, 2013, in their UTM (Undergraduate Texts in Mathematics) series.
Cover of book.
Text (but without exercises) of book. Version of 1 February 2013. Note. This file is not identical to the published book without the exercises. The page numbering is different, and there are some small differences in the text.
Errata (22 November 2017) to the published version.
New online Chapter 13: A glimpse of combinatorial commutative algebra (version of 23 March 2017).
News flash! (4 September 2017) A second edition is forthcoming!