supybot-plugin-create: command not found

Have You tried accessing the binary with the full path?

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 CentOS possible default full paths are:

/usr/bin/supybot-plugin-create - from package: supybot-gribble
/usr/bin/supybot-plugin-create - from package: supybot

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/supybot-plugin-create - from package: supybot

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