If the venue is as dark as you make it sound you will probably have an very hard time getting good shots with the lens you listed. I typically shot indoor sports with nothing slower that an f2.8 lens. Most of the time I opt for faster primes as the college venue I shoot in has decent, but not great lighting.
Stopping action requires fast shutter speeds. 1/250th is the minimum for something like hockey, basketball etc. Slower and motion blur begins to creep in. The only way to get to at least 1/250th in a dark venue is to have fast glass, f2.8 or faster and/or high ISO. With the 18-135 mm f/3.5-5.6G ED-IF AF-S Nikkor my guess is you are going to have to be at 3200 ISO to get close to the required shutter speed.
Keep in mind that you will probably have a lot of noise in your shots at 3200 ISO. If you shoot in raw you can post process a lot of that noise out. This will soften you shots a bit in the process. One of the best ways to reduce noise from high ISO is to have the exposure dead on. That may be a challenge here. With out seeing the venue it is hard to tell.
If you can set a custom white balance before hand, I would suggest that you do so. If not adjust it in post processing. If the lighting happens to be florescent also be aware that you will probably get some color shift in your photos. That is just the nature of florescent lighting.
If you have never shot sports before I would suggest that you set your camera to full time focusing. Canon calls it AI Servo. I do not know what term Nikon uses. Follow the action at all times with the camera constantly focusing on the action. Use one focus point. I normally use the center point.
You have to be prepared to get the shot by tracking the action with the camera constantly focusing on that action. If you don't and see something you want to shoot, by the time the camera focuses the shot is gone. In tough conditions like this it is better to have a shot that is in focus with noise in it than a shot that is blurry because you wanted to reduce the noise with a lower ISO that affected your shutter speed.
As for using some kind of flash, I would suggest that you don't do it. If you are close enough to use a flash in this instance you will probably have to be rink side at eye level. Many venues do not allow flash and if they do not have a prohabition against it, the players may not be too happy with a flash going off in their face. There are ways to strobe an areana but it requires multiple light sources above the playing field typically either bounced or shot over the players heads so you are getting fill light. If you are interested in learning to do so the Strobist site is a good place to learn to do so cheaply.
In large venues the strobe system is usually in the catwalk rafter area pointing straight down on the play area. The local venue here has a large number of installed strobe units specifically designed for that use. I have access to them when I shoot there and they are very nice. They are also very expensive to buy and maintain. That includes insurance in case of an accident.
If you have a chance, go to a pratice or two and get some practice time in yourself. Every fall I start by going to the pre season practice sessions at the local college I shoot for to get some practice time in myself. Sports photography by it's very nature is very demanding both in terms of equipment and on the photographer. It, at least for me is also one of the most enjoyable. Good luck.