12 lead ecg: the art of interpretation is pretty good despite the corny name. They have numerous tracings that correlate well with the chapter contents. They have an interesting layout where you can read through the whole book as a beginner and do novice level interpretations, and then go back and reread certain sections as an intermediate and interpret the tracings as an intermediate, and then do it all over again as an expert. I think it's a pretty clever idea as it forces you to work on a comprehensive interpretation before you start learning all the cool pathognomonic findings or subtle changes.
If you're very confident in your knowledge base and have a particular interest in it, I highly recommend amal mattus 'ecgs for the emergency physician'. It's a two part series that includes 200 strips with real clinical vignettes as well as interpretations and case discussions. The back also has an appendix of ddx for several abnormal findings that is very useful in it's own right. As the title suggests, this is targeted to EM physicians and not med students. That said, the vast majority of the knowledge base that's required to interpret these strips is covered in dubin/Garcia.
