For average reviews from users, you can try this site:
http://www.fredmiranda.com/reviews/index.php
It has all the lenses that you mentioned here.
For sample pictures, try this site:
http://photography-on-the.net/forum/showthread.php?t=141406
This one is kind of like the semi-official-Canon forum.
From what I have read, the Canon 17-55 f/2.8 IS is "almost" the best lens for crop body. This comment is from ppl who have used Canon 24-70 f/2.8L, Canon 24-105 f/4L IS and other third party lenses. Look into their comments than you will see why. It is kind of pricey but it produces L-like Image quality. Also, Canon 70-200 f/4 IS is a little bit sharper than 2.8 IS and even 2.8. with best 4-stop IS system from Canon.
For walk around lens, Tamron 17-50 is also a very good and well accepted thrid party lens. For wide angle, ppl frequently bring up Canon 10-22 and Sigma 10-20. I got the Sigma because it is a little bit cheaper. But if you can affort it, get the Canon.
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本帖最後由 usnameless 於 2008-3-5 15:39 編輯 ]