Here is a list of interesting links of fanpages, regarding mobile cranes.
Ditzj Lots of pictures and information about real cranes and heavy transport.
Kran und Schwerlast Made by Jens Grootoonk from Germany, a site with many pictures of cranes and heavy tranport.
Cranes-Cranes-Cranes Made by Wolfgang Esbruch from Germany with a lot of pictures of cranes and heavy transport.
Trucks-Cranes Made by Eric Konijn from the Netherlands with a lot of pictures of cranes and heavy transport.