Also try to look for kits because with those you can usually find them with atleast two lenses ranging from around 35mm-250mm or so between the two lenses. There are always great deals around. Try Costco because they have some great kits prepared aswell as the 90 day return policy with no questions asked.
Any other questions just pm me about it
BRECK from Matthew Rudolph on Vimeo.
ef-s 15-85 f3.5-5.6 IS USM
720 is is obviously north of your budget but i have spotted this lens in the used store for just about 500 this would be a phenominal starter lens to compliment a rebel, (not to mention at 15mm, shooting video follow cams through the jump lines will look ballin) granted it is an ef-s lens and it wont work on a full-frame body, but your shooting with a rebel and even if you upgrade to a 50d or 7d down the line it will work on them too. bottom line is it is a great starter lens to bypass learning on kit lens with very poor image quality... if you have the budget for it.