Sirius' hiding place

[lmziner]

No: HPFGUIDX 72868

I think we will find out where Sirius was hiding after PoA.  I mean 
JK went to the trouble of mentioning the tropical birds that were 
returning Harry's correspondence.  She also noted that Sirius had his 
hair cut short and looked as if he had gained some weight (when Harry 
speaks to him in the fire while he traveling to Hogwarts).  Could a  
character we have not met yet let him stay with him/her?