Lecture Slides in Principles (General)

McGraw-Hill Higher Education
There is a PowerPoint presentation here for each of the 36 chapters of the Begg, Fischer and Dornbusch introductory textbook Economics. The material has been specially updated for the sixth edition of the book and is available in PowerPoint 97 format.
Confederation of British Industry
This is a collection of presentations given at various CBI (Confederation of British Industry) events made available via SlideShare. They have been authored by members of the CBI or invited speakers from HM Treasury, companies and other organisations. They cover topics such as public procurement, climate change, energy policy, pensions etc. In common with other resources available on SlideShare they are embeddable in other websites, some are downloadable and registered users can comment on the presentations.
Center for Economic and Policy Research
10 lectures by US economists downloadable as streamed video or MP3 audio presentations, with accompanying PowerPoint slides and related papers that pursue the issues in more depth. Two lectures are on growth (Dean Baker, Mark Weisbrot), others on US labour markets (John Schmitt), women in the labour market (Heather Boushey), trade (Mark Weisbrot), intergenerational mobility and life chances (Heather Boushey), the Federal Reserve, asset bubbles and intellectual property (all Dean Baker). The lectures are US-focused and reflect the sometimes market-critical perspective of the Center for Economic Policy and Research, a think-tank founded by Baker and Weisbrot in 1999 with an advisory board including Joseph Stiglitz and Robert Solow (not to be confused with the UK-based Centre for Economic Policy Research).
James D Hamilton, University of California, San Diego
This is a course website for Econ 2 as taught by James D. Hamilton of University of California, San Diego. It contains a course syllabus, problem sets, practice exam papers, slides from each lecture and a series of links to topical economics stories in the news. The course is based on the text by Robert H. Frank and Ben S. Bernanke, Principles of Economics, Third edition.
Addison Wesley

ECON100 offers various resources to support a number of text books authored or co-authored by Michael Parkin. Included are lecture notes (in PowerPoint, HTML or RTF), online quizzes, and news analysis.

Andrew K. G. Hildreth, University of California, Berkeley
Five PDF problem sets, with some answers in separate documents, data tables and slides from lectures are among the resources that support a course on an Introduction to Economics as taught by Andrew K. G. Hildreth of University of California, Berkeley.
Kenneth Train, University of California, Berkeley
This course web page includes problem sets, as well as lecture slides (on market demand), all in .pdf.
Richard Lipsey, Simon Fraser University, Alec Chrystal, Cass Business School
This website accompanies the textbook by Lipsey and Chrystal, Economics, 11th edition and is published by OUP. The site contains a glossary of economic terms presented in Flash, supplemental material (although this is presented as interactive, there appears to be no actual online interaction), online self-test questions, economics stories in the news related to each chapter and a few web links to relevant resources. Further lecturer resources, such as PowerPoint slides, figures, multiple choice tests and VLE / Blackboard content require registration with the website.
Worth Publishers
There are slides here for each of the 34 chapters of the "Economics" textbook by Tregarthen and Rittenberg. They can be downloaded by chapter or all at once. They provide PowerPoint versions of the graphs / images used in the textbook, but no other information.
Stephen Kinsella, Univesity of Limerick
This is a comprehensive archive of lecture videos from Stephen Kinsella, a lecturer in economics at the University of Limerick. It includes courses in financial economics, economics for business, economics of EU integration, international financial economics and occasional on-off lectures, for example those promoting his book Ireland in 2050. The lecture videos show the slides used and are synched with the audio track.
Thinkwell
Thinkwell is a commercial learning tutorial service that supports economics, microeconomics and macroeconomics courses. It consists of video lectures that give simultaneous views of the lecturer and his slides and animations. Online interactive exercises with feedback, review notes, course management tools and a dedicated website for users. Lecturers can customise the course and view the results of interactive tests taken by their students. The materials are available online via subscription and require Flash / QuickTime / Java to load.
WinEcon Consortium

WinEcon is an interactive learning software package for economics, business economics, maths for economics and the range of Sloman textbooks designed to support economics courses. The software provides many hours of tutorial material and includes: all the relevant theory, interactive exercises, self-assessment questions, economics databases and an economic glossary. Teachers of economics can integrate WinEcon into their Virtual Learning Environment (VLE) by creating links from any Web page, Word, Powerpoint or Excel document to specific WinEcon topics. Students working on their own machines can also make full use of these features to link to specific WinEcon screens from their lecturer's Web pages by installing the single user software.