Step 1 - Set your white balance. If you don't want to spend $5 for a gray card, something white will do (sheet of paper, not a t-shirt).
Step 2 - Set your ISO to 1600.
Step 3 - Set your exposure. Turn the dial to M, set the widest aperture you can (smallest #), set the shutter speed off something on the basketball court and adjust based on some test images. (Check the histogram.) If there's really really good lighting and your shutter speed is faster than 1/400, I'd go try a slower ISO and reset exposure.
Step 4 - Shoot away!
![Wink :wink:](./images/smilies/icon_wink.gif)
Oh, a tip when setting aperture. I'm not familiar with your lenses, but the f-numbers after the focal length... if there's 2 of them (i.e. 18-55mm f/4-5.6) then keep in mind that if you set your exposure using the first number say: 1/200 f/4 and then you zoom in you'll be shooting 1/200 f/5.6 and you'll be underexposing by a whole stop.
I really hope you enjoy your D-SLR, mine's really made an addict out of me.
![Very Happy :D](./images/smilies/icon_biggrin.gif)
*edit*
Example of a really well lit gym:
![Image](http://www.microsmithinc.com/BlackRider/wbb_01.jpg)
1/400 f/3.5 ISO 800, 105mm zoom w/ 1.6x crop
(and actually I later went to 1/400 f/2.8 ISO 500, which... I think... is an equivilant exposure, but less noise)