My books are about knitting, so my promotional venues will certainly be different than yours, but here goes:
Schedule book signings, if possible, in conjunction with other events (teaching workshops, attending related conferences). The best venues are the trade shows where the retailers who will (potentially) be selling my book are the attendees. Normal signings at bookstores or retail shows, while they help to develop goodwill, just don't generate enough sales to be worth doing when not in conjunction with some other event. Even so, when I am traveling to a location and know I'll have some extra time, I contact specialty retailers (i.e. needlework and knitting shops) to see if they'd like me to visit or would like to sponsor an event. At the least, I can talk to the store owner or manager and get them interested in my book, which will incline them to stock it and sell it. At best, they will actually get 20-30 people to come by.
Hand out promotional fliers and post cards and do meet-and-greet at high-traffic events related to my book topic (Annual "Knit-Outs" in major cities like NYC and DC) as well as in smaller venues (like workshops I teach).
Mention my book in the catalogs for other products I sell.
Mention my book in e-mail newsletters to my mailing list.
Feature my book on my web site.
Write a regular column on related topic in a magazine, and be sure the title of the book is included in my author blurb at the end of the article.
Monitor major online groups related to my topic and helpfully answer occasional questions or join in conversation. Make sure title of book (and link to it at Amazon or at my web site) is in signature line.
Keep book title and link in signature line for all e-mail.
Note that, for the higher cost items like travel to trade shows and printing of 4-color postcards and fliers, I do not pay for these myself. Either the publisher pays my travel expenses, or I'm doing freelance teaching where the sponsor of the workshops pays for my travel. Occasionally, I'll work an event where I barely break even if it's high visibility or is in a major city where I haven't done any promotion and I feel that it's worth it.
ETA: Provide list of publications to publisher for review copies. Work with publisher to develop press release and develop list of publications to send it to. Be available for interviews.
