UNHCR has been attempting to count the world’s refugees since it was created in. Here you can find data, tweets, maps and news stories from a range of UN agencies. Its stories of Syrian refugees pages adds a more human face to the figures. It also has video and audio footage.
Migration Policy Centre at the European University Institute in Florence has some historic information and timelines of the Syrian refugee crisis. It covers the situation in 2011/12 highlighting EU involvement.
Other useful sources of information on refugees worldwide include the Refugee Studies Centre at the University of Oxford. This has good news coverage with recent interviews about Syria.
RefWorld–– UN system containing reports on the status of refugees worldwide. It includes country files, full text laws and conventions. There is also an extensive directory of links to other useful websites.