Wow - it doesn't happen very often that I have to consult the IANA database to look up a country code; but this one I had to look up.
.ls is run by the University of Lesotho. The IANA database does not list a web site, which probably means that - like in the early early days - domain names have to be registered manually. Lesotho-based ISPs will probably be able to deal with this, don't know if anybody else can.
Probably easiest to contact the person running the registry - you can find details here: