Hi Alisa Mendez!
The project you're working on sounds awesome and ambitious. The details for building a wireless glove are here: http://littlebits.cc/projects/animatronic-hand , but its not available for purchase. The glove basically just detects still finger positions and so wouldn't help much measuring the force of a basketball through.
Getting to all your questions one by one:
I can't say when an accelerometer bit will be released, and unfortunately it is really necessary to begin predicting the ballistics of the ball.
You can definitely use the Arduino bit to display curves on a computer, either doing the calculation on the Arduino or computer. It will be easiest to start with a programming environment called Processing [ https://www.processing.org/ ], or possibly Scratch [ http://littlebits.cc/projects/littlebits-meets-scratch ].
Here is a good example project to start displaying data from the Arduino using Processing: http://littlebits.cc/projects/lissajous-figures
Another approach would be to 'reverse' your project... You could have a Processing sketch display the ideal parabola between the ball and the basket, changing the height of the shooter and the other variables you mentioned in the program.
You could also use pressure sensors and the Arduino to record data during a throw, give that data to Processing, and then mark whether the throw was a success. By repeating, saving, and averaging the pressure sensor data you could build up a subjective profile for each shooter which could help predict future successful shots without needing to know absolute numbers like force, the weight of the basketball, the spin of the basketball, the velocity of the wind, etc. A surprising number of technologies [ e.g. robots, rockets, email filters ] are more 'machine learning' than pre-calculated physics because all the little details, like aerodynamics, that can make big differences.
Thinking of sensor bits you could put near the rim/hoop, I'd suggest pressure, motion, or a light sensor. You can definitely put either a wireless receiver or transmitter there too. Each wireless transmitter has three inputs which work like radio stations, with the wireless receivers 'tuning in' to those three stations. Any wireless receivers near the transmitters will pick up the three signals, just like two people listening to same radio station on two boomboxes.
Its been a long reply, but I didn't want to leave your questions unanswered.