Track Cleaner
The second item that I recommend is using Homosote material cut into small blocks and used as cleaner pads for cleaning by hand. Again, material is not abrasive and will pick up dirt and oils and can be made your self or bought from ppw-aline.com Pads can again be cleaned very easily and last for a very long time.
Rub them on an old piece of carpet or a rag laying on a flat surface.
There are many track cleaner cars out in the market today, some are good and some are not. The only way you will know is to try one or do some research or best of all borrow one from one of your friends and try it out. This is the only way you will really know what works best for you. The two that I mentioned earlier are no brainers, they are inexpensive, easy to maintain and don't need liquid to clean.
Now after all that said, here is the big KICKER about cleaning track that very few talk about! You can use any track cleaner you want, but if you don't clean the wheels on your rolling stock your like a dog chasing it's tail. No matter how much you clean, the minute you start running trains again with dirty wheels you are just depositing the dirt right back onto the rails, hence, dog chasing it's tail!