tough decision on river with TPTK

[xcrack999]

.05/.10 No-limit at Royal Vegas. Only went through one orbit before this hand, so no strong reads. The villain hasn't done anything stupid since I joined the table.

I have $10.00 and Villain has me covered. I am dealt A[img]/images/graemlins/club.gif[/img]K[img]/images/graemlins/spade.gif[/img] in EP. One limper to me and I raise to $0.50, called by villain in LP and the original limper.
Flop comes 9[img]/images/graemlins/diamond.gif[/img]K[img]/images/graemlins/heart.gif[/img]6[img]/images/graemlins/diamond.gif[/img]. Limper checks, I bet the pot (about $1.50), villain calls, and limper folds.
Turn comes 9[img]/images/graemlins/club.gif[/img]. I check, villain checks.
River comes 3 [img]/images/graemlins/spade.gif[/img]. I bet 2/3 pot (about $3.00), and Villain raises all-in. What do I do now? Any comment and critcism on any street appreciated.