I heard that the ottoman empire was the 'sick man of europe' since the early 19th century. Did they produce any of their own weapons for WW1? If not, did they purchase weapons? Or were they very unmodernized compared to other nations?
The Ottoman Empire had reasonably modern infantry weapons before and during the war thanks to their ties with Germany. The infantry had Mauser rifles and German made Maxim guns.
Their artillery branch also contained a lot of modern German pieces, however I am unsure about how numerous these pieces were due to the fact in the Dardanelles Campaign they were using antiquated pieces in the forts.
here is a link to a site about their artillery: http://forum.axishistory.com/viewtopic.php?t=109530
The Ottoman navy, even with the arrival of SMS Goeben never really posed much of a threat to the RN and French Navy. This was not so much of an issue as strategically the Turks were quite well placed. The Dardanelles were effectively a barrier between them and the Med meaning they were relatively safe. (reminds me of Constantinople's great chain in a way)
It wasn't so much the weapons which were unmodernised, it was the whole country. The Army wasn't prepared for war and suffered many language barriers which made communication difficult. However it did see some success at Kut and Gallipolli.