Linux and Nero AAC
Command Line Interface
The free Nero Digital AAC codec package includes Linux binaries for the encoder and decoder as of version 1.3.3 Nero AAC Encoder 1.3.3.
The Windows executables (neroAacEnc.exe, neroAacTag.exe, etc) can be used in Linux via the use of Wine (a windows 32-bit and 64-bit emulator). Users familiar with a command-line interface can use these programs directly after Wine is installed with then necessary dependencies:
$wine neroAacEnc.exe -q 0.5 -if infile.wav -of outfile.wav
Graphical User Interfaces
An easier long-term solution would be to link in the command-line encoder into a graphical user interface.