I wanted to revive this old thread to share my experiences with putting together a low-cost kit specialized for indoor sports. In my case, it's indoor soccer - similar to basketball, though it requires longer focal lengths and lighting is often worse.
XTi Body:
The XTi is a wonderful bargain at this point, and has high-ISO performance that is as good as most of it's successors.
ISO 3200 and Spot AF on the XTi:
I have loaded the CHDK hack, which enables two important features for indoor sports on the XTi: ISO 2000/2500/3200 (especially important for fast action with the f2.8 zooms) and Center-Spot AF (faster and more accurate than other AF modes).
Lenses:
50mm f1.8: must-have lens
100mm f2 USM: wonderful sharp lens with rapid focus
50-150mm f2.8 Sigma HSM Version II: appears to focus as fast as my Canon 70-200/2.8 IS and half the weight; not in production any more, so it requires some searching, especially to find the Version II of the lens which is improved optically. Lack of IS is not important, because you generally want to use a fast shutter speed to stop motion.
Body and 3 lenses for less than $1000 ... indoor sports performance: priceless!
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