s3get: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/s3get - from package: libnet-amazon-s3-tools-perl

You may install the required package with command apt-get install {package}

Error in other languages:
s3get: bevel nie gevind nie
s3get: comandă negăsită
s3get: comando não encontrado
s3get: commande introuvable
s3get: command not found
s3get: käsku ei ole
s3get: không tìm thấy lệnh
s3get: komanda nerasta
s3get: Kommando nicht gefunden.
s3get: kommandot finns inte
s3get: komut yok
s3get: nie znaleziono polecenia
s3get: níor aimsíodh an t-ordú
s3get: no se encontró la orden
s3get: no s'ha trobat l'ordre
s3get: opdracht niet gevonden
s3get: parancs nem található
s3get: perintah tidak ditemukan
s3get: príkaz nenájdený
s3get: příkaz nenalezen
s3get: команда не найдена
s3get: командата не е открита
s3get: 命令找不到
s3get: コマンドが見つかりません