No test has been published which enables anyone to identify the "best" (the various expansion tests that people publish are interesting, but not really relevant to real-world "stopping" functionality). You would do well with any of the recent bullets from major makers. Look for Winchester Rangers, Speer Gold Dots and Remington Golden Sabers. Look for a 124-grain +P hollowpoint at a minimum. And test them to make sure that they function well and are accurate in your gun - guns are very individual with what they like sometimes.

Based on having done this, I carry Speer 124-gr +P short barrel Gold Dots in my 3" CZ RAMI and Winchester 127-gr +P+ Ranger (RA9TA) in my 4" Sigma. Your 909 (nice gun) has a 4" barrel . . . .

The most important thing is that you shoot your gun accurately and place your shots into the vitals. This requires your gun to function, it requires shot-placement, and it requires adequate penetration. (Note that I did not say "expansion": expansion is gravy, but it's not an essential. The best thing that expansion does for a 9mm is keep the bullet from coming out of the back of the bad guy and going through the school bus of kids behind him.) Any decent 9x19 JHP on the market should be able to handle this from your 909. There is no magic bullet, but you should be able to do well with any number of them out there.