Thank you for reviewing my question.

I am looking for an accurate and easily reviewable source, web or
print based, that allows me to easily track the Top 100 songs in the
US for any given week since Jan 1955 until the present day (preferably
updated weekly on an ongoing basis).  Billboard or Cash Box is
preferred, although other sources are acceptable as long as they are
accepted by the music industry as a reliable standard for this
information.

I have used various web pages in the past that catalogued this
information, and worked adequately enough, but my primary sources have
disappeared and are no longer available now.

I am most interested in the best web-based sources of this information
that are easily navigable yet complete in nature, but also appreciate
any leads on books in print that contain similar information (and
preferably not at a princely sum).

A tip will be offered for excellent research and scholarship.

Thank you!

At recordresearch.com you can buy a book that lists the Top Ten per
week from 1955 through 2000.  Other info is available about the Top
100.  Good luck.