Does anybody know how can I calculate the lateral torsional buckling of a cruciform steel shape, i want to do it according to the AISC 2010 but i can not find any mention of this kind of shape.
These aren't simple cruciforms - they are crossed "I" shapes, and warping effects may come into play. It is certainly not a common shape for beams. What is the specific application you're using it for?
If IMCA is providing geometric information on these, they might also have some design guidance for you.