The basic first steps will be pretty much the same when researching your family
history in the United States of America, but in addition there are many useful
websites specific to the USA which you will find extremely helpful.
Undoubtedly the premier site in the United States is USGenWeb project,
whose motto "keeping Internet Genealogy Free" speaks volumes. Most
of what you will need will be found on this site.
The federation of Genealogical Societies website is
definitely to be recommended.
The Ellis Island website contains
much information about the arrival of immigrants, including a passenger arrivals
An excellent website - General
U.S. History - that journals the history of the USA. It contains information
on the colonies, has a timeline, maps etc etc. A must visit site that will
help you to understand who your ancestors were and what they were about.