When starting a business plan or a forcast we need accurate market data,how can we collect such data in the middle east,are data collected accurate?

Several MNCs have already got this job done for this region and datas are available with them. Market research organisations like IDC, Nielsen, etc have done it for the said region. MNCs use these data in spreading their activities thru their channel partners for assessing business potentials.

As per my experience, this is very hard to do. Sources are rare and reliability is uncertain.

This is a good question and a difficult one to get results for

Middle-East is somehow missing in the global business radar screen. 

Businesses and organizations talk about  USA and Canada (North America), Europe, Far East, China, India, Japan , ...  etc etc ...

In the middle-east and for middle-east markets, there is scarcity in market research ..  Hence , business planners take market research from other markets as their baseline and try to tailor it according to known facts about the geographies/territories they want to target in the middle-east.

Other business entities may hire research firms to do special customized market research per their requirments and needs.