Where did Minato learnt Rasenga and ... ?

[Kages]

He got the idea from TBB

 

[Yashiro]

Minato created the RASENGAN

 

[vicstrike]

he had fought nine tails once before konoha attack....remember raikage himself said,"so he is one who singlehandedly prevented the recovery of ninetails".
he may have saw tbb that time.

 

[bayosys]

he had fought nine tails once before konoha attack....remember raikage himself said,"so he is one who singlehandedly prevented the recovery of ninetails".
he may have saw tbb that time.

May be