Is there some kind of application for converting between various formats of disk image files (.img, .iso, ...)?
MagicISO can do that. Not free though...
Simple and Intelligent
MagicISO is a powerful CD/DVD image file creating/editing/extracting tool. It can open / create / edit /extract CD/DVD image files, and it can convert bin to iso and back. as well as make ISO file from DVD/CD-ROM or hard disk, and handle bootable information at meanwhile.
Support all known CD image type
It can also convert BIN or any other format file created by CD burning software (Such as Nero-Burning ROM, Easy CD Create) or virtual DVD/CD-ROM driver software (such as Daemon-tools) to standard ISO format.
Convert image files between ISO/BIN and other formats. PowerISO can convert almost all image file formats to standard ISO format file.