Nikon 18-105mm or 55-300mm?

I found both of these lenses used online for around the same price and I'm torn with which one to get. I've looked at reviews and samples of video and images online. I think I like the 55-300mm. What are opinions from experience? What i'm looking for is sharper imaging with action shots

Action shots? The 300 won't do that except in broad sunlight because the f/stop is too high. It would be a good distance lens though if that's what you're after.

However, I would take issue with the "used" part of your equation. Buying used, at least in my opinion, is never a good idea because you never know what you're getting. Does the lens work?
Has it been wet? So many questions.

These lenses serve two different purposes. If you review the webpage below, and look at what each focal length looks like, you will immediately see the purpose of each:

http://www.althephoto.com/concepts/lenses.php

You are going to need to go to a f/2.8 constant aperture minimum for a decent sports-action lens. And those are so highly sought after, even used ones cost almost as much as new ones.

The least expensive good sports telephoto is the Sigma 70-200mm f/2.8. But even it's $1, 200. Fact is - good sports/action lenses are expensive.

Instead of used, consider refurbished. A refurbished lens is more or less new, and is reconditioned by Nikon factory (at least if you buy it from the correct store; Adorama, B&H, etc.), and carries a 90 day warranty - which is better than used.

Refurbished 55-300mm ($239):

http://www.bhphotovideo.com/..._5_6G.html

Refurbished 18-105mm ($259):

http://www.bhphotovideo.com/...6G_ED.html

I have purchased refurbished lenses from Roberts and Cameta as well. They are also Nikon refurbished. Be careful though for other stores as they may be "seller refurbished" rather than "factory refurbished".

Every refurbished lens I have ever bought looked like new.

It is pointless to look at sample shots taken by the same equipment online. You are not guaranteed to get the same results because picture quality (sharpness included) depends mostly on user skill. The lens is only a tool.

If you already have the 18-55mm lens, you would be better off getting the 55-300mm for greater versatility. You will be increasing your overall range to 18-300mm.

You will never be satisfied with a 105mm. It's too short for pulling distant objects closer to you. 105mm is best for taking details of objects that are just beyond your reach, not exactly very far.