Not much is known about the place, but then, there's not much there. Klatchistan is basically an uninhabitable region covered with ferocious desert located on the continent of Klatch. In Mort, a "promising" war (in terms of number of fatal casualties) is fought there, but Mort opts for a more promising assassination. One wonders if the effect of Death being absent is what caused the great amount of interest the Gods had in the war (as mentioned by Anoia in Wintersmith).
It was one of a number of regions patrolled by 71-hour Ahmed, and where he ended up after the events of Jingo. After Prince Cadram's plans were ruined he fled here. Due to Ahmed's rough brand of justice, Cadram's lifespan is probably not going to be too long.
Klatchistan apparently produces Klatch's supply of pedigree hunting dogs.
The Compleat Discworld Atlas expands on knowledge about this country, noting it is divided into Klatchistan proper and Upper Klatchistan, following a brief civil war during the Year of the Prawn. Klatchistan, the more rimwards state, is bordered by Vanglemesh, Ushistan, Betrek and Istanzia. The border with Vanglemesh is defined by the course of the Herelayan Mountains. Upper Klatchistan has a shared border with Klatchistan defined by the course of the River Al'Paka, and is elsewhere bordered by Vanglemesh, Zlobenia and the more debated regions of the Main continent widdershins of the Morpork Mountains. An Emir rules the country, and apparently the national currency consists of goats. The river Al'Paka is the only green and fertile land in Klatchistan, and rivalry over its control led to the division of the nation into two countries, each controlling one river bank. Klatchistanian carpets are particularly sought after in Ankh-Morpork, and sell well, once the sheep and goat dung is cleaned off. These days, the national sport, reminiscent of polo, is played with a wooden ball, known as the b'once. Less friendly games revert to the earlier version of the ball.
The civil war which split the country in to two separate countries parallels a number of historical events on Roundworld but most resembles the 2005 war which would later lead to the independence of South Sudan from Sudan in 2011.