You can also browse through the lessons from the following Inventor 8 courses and watch sample lessons from each course.

Inventor 8: Accelerated Productivity
Inventor 8: Mechanical Design
Inventor 8: Sheet Metal Design

Accelerated Productivity Lessons
(Click highlighted lessons to watch them.)
Introduction
About Getting Started
The What To Do Window
Create a Project
Overview of the User Interface
Create a Sketch
Extruding a Profile
Editing Profiles
Sketches vs Profiles
Constraining Profiles
Creating Profiles From Solids
Default Work Planes
Revolve a Feature
Trick for Constraining Sketches
Constraining the Axis of Revolution
Projecting Geometry
Creating Work Planes
Extruding to a Plane
Sharing Sketches
Construction Lines
Centerlines
Mirroring Features
Circular Feature Array
Rectangular Feature Array
Application Options
Creating Holes
Creating Hole Patterns Part I
Creating Hole Patterns Part II
Threaded Holes
Fundamentals of the Shell Command
3D Construction Stage I
3D Construction Stage II
3D Construction Stage III
Ribs
Lofts
Loft Conditions
Loft Transition and Point Mapping
Lofts with Rails
Sweep
Coils and Springs
Parameters
Linking Excel Spreadsheets
Threads
Conclusion