Demonstrating on my work computer how the iPod works with iTunes, I connected my iPod to a new installation of iTunes which immediately started formatting my iPod for the ‘new’ installation of iTunes. I was able to stop the process before all my music was lost, but about 75% of the songs are gone. Due to the size of the music, I do not keep backup copies on my computer. Is there a way to recover these erased songs, or are they gone forever?

When researching your question I encountered other users who experienced the same issue when synching their iPod with a new installation of iTunes. Unfortunately there is no easy way to recover the files which have been lost. Your best option is to configure the iPod to act as an external hard drive (so the iPod appears as a hard drive when connected to the computer) and then use data recovery software to search and (attempt to) restore the deleted files. This process essentially treats the iPod just like any other hard drive and attempts to recover deleted files. Be aware, to accomplish this task you will likely need to purchase data recovery software. Searching Google for terms such as ‘recover deleted files ipod’ yields results from software which claims to be able to recover deleted files. However, I have not used any of this software, so cannot offer any recommendations or comment on any of the software and their effectiveness. That said, many of these software packages allow you to download a free trial which will scan the drive and detect deleted files which could be recovered, and you then need to purchase the software to actually recover the files. While there is a chance the data recovery software cannot recover the detected files, this will at least allow you to evaluate different software and determine which would be the best candidate for purchase. Be warned, you can only recover files if the space they occupied has not been overwritten. If you have already copied new files to the iPod, it is likely the space occupied by the deleted files has been overwritten and you cannot recover some (if not all) of those files. So, in situations where something has been accidentally deleted from a drive and you intend to recover the data, you should not use the drive before attempting to recover the data, to avoid any risk of overwriting the deleted data.