I am looking at lenses for the Digital Rebel XT. What is the difference between:

Canon EF 75-300mm f/4-5.6 Zoom Lens III

which can be seen here:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4687&item=7514323184&rd=1

-- it's pretty big.. says 4x.

... and this one: Canon EF 18-55mm f3.5-5.6??

Someone here said the 18-55 should be like 3x, but it's a lot smaller of a lense.

I also see this one for $99:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4687&item=7512615854&rd=1

It looks long, but less circumfrence of the circle, but says it's "This 500mm telephoto lens is great for nature and sports photography. The amazing power of this lens gives you the equivalent of looking through a pair of 10x power binoculars."

That last one is a Canon mount lens, not a Canon lens, so you never know if it is a Coke bottle with a tripod mount or a wonderful lens.

I am looking at lenses for the Digital Rebel XT. What is the difference between:

Canon EF 75-300mm f/4-5.6 Zoom Lens III

which can be seen here:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4687&item=7514323184&rd=1

-- it's pretty big.. says 4x.

... and this one: Canon EF 18-55mm f3.5-5.6??

Someone here said the 18-55 should be like 3x, but it's a lot smaller of a lense.
It's like comparing a screwdriver to a saw. You would you each for different situations.
* The first is basically a wide angle lens with moderate zoom capability
* The other has no wide angle ability and MUCH farther reach (telephoto)

Take into consideration, too, that you're about to invest several HUNDRED dollars into a piece of gear (plus filters, memory cards, a case, blah-blah-blah) that will basically RECORD images based on the lens you've selected.

If you get a cheap lens, your brand new, high-tech digital body will record crappy images. What's the point in that?

If budget is an issue, wait until so you can afford a high quality lens.

Budget is not an issue. I'm atleast gonna go with the Canon lenses.

I was just throwing the $99 one in there for comparison because I am confused as all hell. LOL!

I'd be happy with something that gets me about 10x and I can get a 2x telephoto that goes on top of that, eh?!