I will give you a link to one of Canon's excellent telephoto zoom lenses - a favorite of many people here. It's the Canon 70-200mm/f4. With the crop factor on the Rebel - the 200mm becomes 320mm (of course the 70 becomes 112). This is a great all around lens: sharp, beautiful color/contrast. Price is $549 after rebate. Excellent price.

the f4 means it isn't good for low light situations. However, the 70-200mm/f2.8 is over $1,000. Here is a link with all the info on this lens.

http://www.bhphotovideo.com/bnh/cont...=183198&is=USA

There are many options - depending on what you will be using it for - and inside/outside, budget, etc.

Liz