Need some help comparing Nikon wide angle lenses for a DX shooter?

So I'm a bit of a photography newbie, but I'd love some help in understanding the differences in these 2 Lenses.

The Camera I'm using is Nikon D5000 and my favorite thing to shoot by far is landscapes.

AF-S DX Zoom-Nikkor
12-24mm f/4G IF-ED

I've heard some pretty great things about this lens, but I'm not exactly wanting to spend tons of money on a lens.

AF-S DX NIKKOR
10-24mm f/3.5-4.5G ED

This is the other lens I've considered because of the lower price and fairly comparable specs, But I'd love some input on how different they actually are.

Thanks all.

Added (1). Also, I'm wondering how safe it is to buy used lenses from the Nikon website.

Added (2). Also, I'm wondering how safe it is to buy used lenses from the Nikon website.

The lenses you buy from Nikons website are actually refurbished, so not "used" in the sense you may be thinking.

I have used the Nikkor AF-S 12-24 mm lens since 2002 and it is a great lens for use with any DX camera.

The 10-24 mm, of course will give you a wider angle of view, so might produce a better landscape and certainly it will allow you to shoot indoor architectural shots in smaller rooms than the 12-24 mm (see link below)

Tokina makes some excellent third party lenses for Nikon. Look at the Tokina 11-16mm f/2.8 AT-X116 Pro DX II.

Any wide-angle lens which is at low price and which covers a fairly large range must be suspect in quality, even if made by Nikon. Very wide-angle lenses are hard to design, therefore seek one that covers only the range you need. Possibly the Tokina 11-16 would be better; I think that Tamron also makes one of 11-16mm, at constant f2.8.

Presumably you already have a kit lens of around 18-55mm, which covers the "medium wide-angle" aspect.

To see how these lenses compare in optical quality, go to http://www.photozone.de/...lens-tests