Reddit reviews Mastering Trademark and Unfair Competition Law (Mastering Series)

This could be worthwhile, it's $10 for the kindle edition, but it is a great book on trademarks. It is a good mix of not being a casebook but also providing cases of authority.

Outside of that, try narrowing your search down into the issues of trademark law you are looking for. If you have any specifics in mind, I may be able to help further.