I'm also a strong advocate for getting your book in catalogs. Once you convince them to carry your title, you'll likely sell to them year after year. Sending complimentary review copies and news releases. We sent out 463 free copies of Jump Start Your Book Sales. Major publishers don't do this, so it gives self-publishers a real advantage.
Nothing sells the book to reviewers, chains, and wholesalers like the book.
It is easier technically, but more competitive. Many authors are discovering self-publishing. Printing on Demand is beginning to play a role and ebooks are starting to penetrate the scene. The key is promotion and publicity. Ingram wants to know YOU will drive traffic into the stores with reviews, author interviews, feature stories, etc.