Supercourse-Principles of Epidemiology
http://www.pitt.edu/~super1/collections/collection33.htm  (list of courses).
Lectures on Principles. http://www.pitt.edu/~super1/collections/collection35.htm
Review lectures on 
Introduction to epidemiology, Part 1, start with slide 6 (the learning objectives of this slide apply to each of the following PowerPoint sets, the textbook by Gordis is good one, any of the introductory texts on epidemiology will serve you both for this course and when you start medical school.) The most important slides in this set are 18, 19, 24 and 25.
Introduction to Epidemiology Part 2, start with slide 7.  Most important slides in this set on numbers 8, 16, 28, 29, 34-38.
Understanding Analytic principles, Part 1.  Start with slide 5, most of this is a summary of biostatistics that you should have learned earlier and is a good review before you start the course.
Part 2.  This also is mainly biostatistics but will be important in reviewing the various research studies we will discuss during the course.  The most important part of this PowerPoint set starts at slide 20 and will also be very useful in the discussions we will have each week on research topics.
 Case control. Part 1.  The most important part of this since slides is that of comparing incidents and prevalence and in how to select cases of disease for study.  The selection of controls is particularly important in the area in which most research fails poorly.  Also look at the comments regarding bias in control selection. 
Cohort Studies Part 1.  Slides 1 through 20 are the most useful for this set of slides.
Descriptive epidemiology part 1.  This is very good set of slides and important to hypothesis development.
Differentiate association from causation. This is an important concept and one that many researchers get wrong and which are frequently confused by the readers of the general press. 
Review measures of public health impact.  These are useful concepts and should be scanned with interest.
Review lectures on screening.  This is an important topic currently as there is a lot of evidence that much of today’s screening is overdone and results in more harm than good.  Start at slide 4.  The evaluation of testing at slide 19 is of particular importance to the chronic disease course, and slide 26 is probably the most important slide in this set.

Feel free to scan the other lectures.  I’m not sure what the Gordis’s textbook is in the TML  library.  You will need an epidemiologic textbook once you start either medical school or the mph course and most of the introductory textbooks on epidemiology are just fine.