In the book online self-publishing world, some M&A: AuthorHouse, one of the largest in the sector, has bought rival iUniverse, a self-publisher based in Lincoln, Neb., for an undisclosed sum. Author Solutions is owned by Bertram Capital Management, a private-equity firm, reports WSJ. Terms were not disclosed. The companies said AuthorHouse is focused on the service side of the business, including layout and marketing, while iUniverse has a broader set of editorial services. More on the deal here.

The two are competing against competitors as Amazon.com and Lulu.com. Amazon moved into self-publishing in April 2005 by acquiring BookSurge, and last month its CreateSpace unit launched an online books-on-demand service…authors can sell their books on Amazon.com as well.