I would like to know how many new motorcycles registrations have been
established by State and by year 2000,2001,2002 ans 2003 year to date
if this is available. We market custom made choppers and would like to
know how many motorcycle people are out ther

DJVallauri --

Information on motor vehicle registration, including data on
motorcycle registration, is available annually in the "Highway
Statistics Annual" published by the U.S. Federal Highway
Administration.

It includes a breakdown by state and data on useage of motorcycles as
well.  As you can imagine, California motorcycles get used the most. 
The data hasn't been accumulated past 2001 yet but you will find data
back to 1992:
U.S. Federal Highway Administration
"Highway Statistics Publications"
http://www.fhwa.dot.gov/policy/ohpi/hss/hsspubs.htm

Best regards,

Omnivorous-GA