Several users have reported an issue in which iPhones and/or iPods will not appear in iTunes after the update to iTunes 9.1.
In most cases, this issue can be resolved by deleting the following file
Failing this, you may want to peruse the fixes available in this Apple Knowledge Base article.
Obsessed with tech since the early arrival of A/UX on Apple, Sudz (SK) is responsible for the editorial direction of AppleToolBox. He is based out of Los Angeles, CA.
Sudz specializes in covering all things macOS, having reviewed dozens of OS X and macOS developments over the years.
In a former life, Sudz worked helping Fortune 100 companies with their technology and business transformation aspirations.