What type of filter to buy for camera lens?

I have the Nikon D60 with the standard AF-S DX NIKKOR 18-55mm f/3.5-5.6G VR Lens that comes with the camera. I would like to take better outside photos. The sky is always washed out. I want a nice blue sky and white clouds that aren't too hot. Do I just get a polarizing lens filter? Also, I would just get size 55mm, since I have the 18-55mm lens, right? Any brand recommendations? Would like to spend less then $40.
I'm an amateur… Don't make fun of me.

You need a circular polarising filter. The diameter you need for that lens is 52mm.

Here's one;
http://www.warehouseexpress.com/buy-hoya-52mm-shmc-pro-1-digital-circular-polariser/p1011126

Don't go for cheap filters - they are optical inferior & can leave nasty colour casts on your images.

What you are encountering is the difference in dynamic range between the sky and the land. This can be delt with by proper metering and setting your camera yourself. For example, when in Aperture priority set the camera to spot metering. Set the aperture to f8 or f11 and point at the ground. See what shutter speed you get. Now do the same for the sky. Add these two together and divede by 2. Set the shutter speed to what you get from that.

If that does not do it for you then graduated neutral density filters may be for you. These are filters where only the top half is colored.

I ran into the same problem some time ago and solved it by ordering a kit of filters. I went for Cokin's h-250 kit which has all you need to get started for a decent price. Just get a p-series ring for 52mm as well
Now people will tell you that there's much better filters out there than Cokin and they will be right. However, other brands will sell you not even a single filter for what this kit costs and it is good enough to get started and to find if this works for you.

I wrote a little something on my blog about my first steps with these filters: http://wijnands.blogspot.com/2009/06/graduated-neutral-density-filters-part.html

A polarizing filter is all you need, though you could try graduated grey filters to 'hold back' the sky.

Another way is to bracket shots and merge in software, Google HDR to find out more.

Have you tried adjusting the settings for the aperture and shutter speed? I have a Nikon and it always lets too much light in so I never use the auto-settings.
A UV filter is absolutely necessary and if the sun is really bright then a polarising flter might help. I'd try playing around with your camera settings before buying a filter.

Definitely a circular polarising filter…

A polarizing filter can be quite handy but in the situation you describe it may not be the right choice.

You may need to use a Neutral Density filter or do HDR.

http://www.mountainlight.com/filters.html
http://en.wikipedia.org/...ge_imaging

Anyhow, everyone should have a polarizing filter in their bag.

A circular polarizer (CPL) filter will get you the awesome blue skies with contrasty clouds.

A graduated-neutral-density (GND) filter will balance the overexposure of the sky with the foreground.

Unfortunately, you can't find good quality filters of either type for less than $40. More like $75 in the filter size you need for that lens. That lens takes a 52mm filter (don't worry, lots of people confuse the filter size with the focal length).

If you're only going to get one, I recommend the polarizer. Its effects can't be done in Photoshop. A GND filter can be mimicked by taking two exposures-one for the sky, one for the foreground-and blending them in Photoshop afterward.

Polarising filters bring out the colour in mainly skies, they also stop reflection.
Check the "mm" of your lens by looking at the ring around the front of the lens and then buy the suitable filter,

If you want to darken the sky while keeping the foreground natural get a graduated filter.