this should work if you dont want it kicking ops, halfops or voiced users

on *:TEXT:*:#: { 
  if ($nick isop $chan) || ($nick ishop $chan) {
    if (!sp == $strip($1)) { 
      if (!$2) { eis | .msg $chan ?spam command: ?spam on/off/status }
      if ($regex($strip($1-),/on|off/i)) { set $+(%,sp,$chan) $2 | .msg $chan Spam Protect is now $($+(%,sp,$chan),2) $+ . }
      if ($strip($2) == status) { .msg $chan Spam Protect is currently $($+(%,sp,$chan),2) }
  } }
  if ($regex($strip($1-),/http|www|com|org|net/i)) && ($($+(%,sp,$chan),2) == on) { 
    if ($nick isop $chan) || ($nick ishop $chan) || ($nick isvoice $chan) { halt }
    else {
      if ($+(%,spam,$nick) == $null) { set $+(%,spam,$nick) 1 }
      else { inc $+(%,spam,$nick) 1 }
      if ($($+(%,spam,$nick),2) == 3) { unset $+(%,spam,$nick) | ban -k $chan $nick 2 Spam/Advertising. | .notice $nick You have been banned from $chan for Spam/Advertising. }
      .msg $chan $nick - Spamming is not allowed in this channel.
    }
} }