hcitool: 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 CentOS possible default full paths are:

/usr/bin/hcitool - from package: bluez

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

On Debian possible default full paths are:

/usr/bin/hcitool - from package: bluez

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

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