How to take (blurring the line) photos on a nikon d5000?

Pictures like these
http://www.thomoconnorphotography.com/web-content/PortfolioGallery/PortfolioPage.html

on a nikon d5000

Those are just simple long exposures. Put your camera in S mode, (means Shutter Priority). Manually set the shutter speed to about 1/20. Set the ISO to 100. The camera will pick the aperture to match the conditions. After taking the photo, check your monitor. If too blurred, make the shutter speed a little faster, such as 1/30. If you want then more blurred, slow the shutter down some more, such as 1/10 or less.

It's a technique called panning. Blurring the lines is that guys title for that one photo. Youtube has tutorials galore

Most of the photos are nothing more than slow shutter speeds and the images got blurred because the camera was hand held. Many people do it All the time, but hardly save them. In a few cases the photographer also used the slow shutter speed in conjunctions with motion, and panned with the movement as the shutter went off.
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Set your camera on S - Shutter Priority and use your thumb wheel to turn the shutter down to anything less than 1/30th and down to 1 full second. The longer the shutter is open the more blare.
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In daylight you will want to slow your ISO down as well, but here you can experiment.
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It's really quite easy and as I said, most people throw these shots away but this person made a art out if.
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They look to me like pictures made by intentionally moving the camera while also panning with the subject.

All a slow shutter speed would do is cause any moving subject to be a continuous blur. In the examples shown there's simply too much detail for them to have been made with just a slow shutter speed. Look at the bicycle frame and the wheels.

So turn the VR on the lens OFF, use a low ISO, use Aperture Priority and keep stopping down the lens until you get a slower shutter speed and then move the camera slightly while panning with the subject or during the exposure of a stationary subject.

Here are a couple of tutorials on panning:

http://www.digital-photography-school.com/mastering-panning-to-photograph-moving-subjects

http://www.ehow.com/...raphy.html