The Information Technology Infrastructure Library (ITIL), is a set of best-practices for IT service management (ITSM) that focuses on aligning IT services with the needs of the business. IT Asset Management (ITAM) is a cornerstone of the success of ITIL. To clarify the best-practices of ITIL, if not the overabundance of acronyms, you can download the 2011 edition of the best practices guide.
As the ITIL website states, "ITSM is driven both by technology and the huge range of organisational environments in which it operates, it is in a state of constant evolution. Best practice, based on expert advice and input from ITIL users is both current and practical, combining the latest thinking with sound, common sense guidance."
Aside from the best practices guide, you can also read a white paper on the basics of ITIL.