Modern Vespa officially recommends the MSF Basic Rider Course (or BRC) as the single best way for new riders in the US to start riding. The MSF BRC courses provide beginner riders with instruction and practical riding skills, and also provides a helmet and a motorcycle for the duration of the course. In many states, passing the MSF course gives the student an automatic waiver for the DMV riding test. Check with your local MSF organization.
While MSF is predominantly motorcycle-oriented, they have recently begun recognizing scooters, and are offering a pared-down scooter course in some areas: MSF Scooter School
They also have an online library with a variety of materials, including a free booklet with riding tips for scooterists: MSF Scooter Tips booklet (pdf)
Even if you've been riding for some time, there's always something new to learn. Increasing numbers of seasoned riders are taking the half-day Experienced RiderCourse to hone their skills and fine-tune the mental skills needed for survival in traffic. This course is conducted using your own scooter or motorcycle.
The Motorcycle Safety Foundation and The National Safety Council have partnered to provide an Internet-based interactive Motorcycle Defensive Driver Course. Based on the Motorcycle Safety Foundation's curriculum, this two hour program covers vital safe riding information for educating riders. This is not a substitute for the Basic Rider Course, nor does it provide a waiver for the DMV driving test. In many states this can be used for motorcycle insurance discounts. Check with your insurance carrier to see if you qualify. (fee charged to take online course)
This program is designed to teach basic, intermediate and advanced skills to students. This training covers much of those taught to police motor officers. It is a highly tactical and defensive training environment, and very challenging.
Total Control Advanced Riding Clinics
Unfortunately for experienced riders, there is a large gap between the Motorcycle Safety Foundation's Experienced RiderCourse (ERC) and the many racetrack schools around the country. Many riders are interested in improving their skills but are unwilling to take on the additional risks associated with a high-speed environment. If you fit into the "I'm interested, but" group, you're not alone. In fact, if you add up all the attendees of all the race schools together, they only represent a tiny percentage of street riders. This is not to say they are not good schools. To the contrary, they have much to offer. But they are not for everyone. Fortunately, Lee Parks' Total Control Advanced Riding Clinic (Total Control ARC) has a solution for those experienced riders "caught in the middle," as well as those track-day junkies and racers who want to be able to further enhance their skills in a controlled environment with expert instruction.
In Queensland, South Australia and Western Australia it is still legal to ride a motorcycle or scooter up to 50ccs with a (car)driver's license, however, the motorcycle licensing courses give valuable information on defensive riding techniques and improving your safety on the road.
The following links will take you to the details for your state:
New South Wales
Australian Capital Territory
The Motorcycle Safety Foundation's Guide to Motorcycling Excellence: Skills, Knowledge, and Strategies for Riding Right (2nd Edition) (Paperback), Whitehorse Press; Second edition (October 1, 2005)
Proficient Motorcycling: The Ultimate Guide to Riding Well (Paperback)
by David L. Hough, BowTie Press; First edition (April 2000)
Street Strategies: A Survival Guide for Motorcyclists (Paperback)
by David Hough, BowTie Press (November 2001)
More Proficient Motorcycling: Mastering the Ride (Paperback)
by David L. Hough, BowTie Press (March 2003)
How To Ride A Motorcycle: A Rider's Guide to Strategy, Safety and Skill Development (Paperback)
by Pat Hahn, Motorbooks; First edition (October 29, 2005)
A beginner's manual especially geared to the needs of entry-level riders.
Group Riding from the American Motorcycle Association
Group Riding Guidelines for Street Bikes from the Master Strategy Group.
Motorcycle Etiquette from the New Jersey Motorcycle Cruisers organization
Group Riding Guide from the Toronto Moto Scooter Club.
The Hurt Report AKA Motorcycle Accident Cause Factors and Identification of Countermeasures
This is a summary of the findings of the landmark 1981 study of motorcycle mishaps in the Los Angeles, CA area. The full report is huge and must be purchased, as detailed at the beginning of the page.
The MAIDS Study of Motorcycle mishaps in Europe (1999-2000)
This investigation was conducted on 921 accidents from 5 countries using a common research methodology.
Version 2.0 released April 2009
Registration required to view, but registration is free.
Washington State (US) Motorcycle Task Force Report June 2006
A report on the causes and circumstances of fatal motorcycle accidents in Washington State over a multi year period.
(US) NTSB Public Forum on Motorcycle Safety
This forum was conducted in Sep 2006. A wealth of information was presented and is available on line.
(UK) Department for Transport report, In Depth Study of Motorcycle Accidents, Nov 2004
A sample of 1,790 PTW accident cases was considered, including 1,003 in detail, from Midland police forces, involving motorcyclists of all ages, and covering the years 1997-2002 inclusive.
Motorcycle rider conspicuity and crash related injury, Wells at al, 2004 (Auckland, New Zealand)
A study of whether the risk of motorcycle crash related injuries is associated with the inability of the motorcyclist or his vehicle to be seen by other road users.
Fatal Single Vehicle Motorcycle Crashes, The National Highway Traffic Safety Administration (US), Oct 2001
A study of fatal mishaps in the years 1990-1999, identifying causative factors.
(AU) Monash University Accident Research Centre.
Research reports on motorcycle accidents including hazard perception by inexperienced motorcyclists.