Canon Camera Price
What is a decent telephoto zoom for Canon Digital Rebel Camera 250 – $ 500 USD price range (if any)?

This is for a photographer amateur who wants to be able to do things like zoom in birds in the trees / receive decent shots that a batter in a baseball game seat stadium, etc.

I'd recommend Canon EF 70-300mm f/4-5.6 IS USM ($ 482). This objective is highly valued in the various examinations. The image quality is good 70-200mm. It also has image stabilization helps reduce blur especially in shooting long focal length.