lasblock: 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/lasblock - from package: liblas-bin

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

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