First do NOT buy a non-Canon lens. Tamron, Sigma, Tokina - doesn't matter. You need top notch AF performance and all of the 3rd party lenses fall short in that area. Shoot, even some of the Canon lenses fall short in that regard.
Best bang for the buck lenses for indoor HS basketball with a crop body are the 85 f/1.8 USM, followed by the 50 f/1.4 USM. I could easily shoot an entire game with my 7D-II and 85 f/1.8 and get plenty of keepers.
Shoot from under the basket. Manual mode. Shutter speed 1/640 or faster, aperture f/2.0, ISO whatever it takes to get a good exposure (histogram pushed to the right without clipping). Don't trust your light meter or auto mode since you'll be looking up into the lights and will end up with under exposed images.
Servo focus mode, center point only, high-speed repeat mode.
Shoot in RAW mode so you can do the NR you'll need and the custom white balance to get the shots to look correct (not orange or green).
Shoot for unblocked faces and the ball visible in each shot.
Piece of cake, right?
Oh, wait, there are 8 pages to this thread. Oops. I read the first one only. I'm probably saying nothing new.