There are lots of great tools to help you make decisions. For brainstorming and prioritizing options, you can use anything from Post-it notes to sophisticated tools such as DecisionLens and the Thinking Dimensions tools by Kepner-Fourie.
Once you decide, you need a way to tell others about it. There are also lots of tools for spreading the word, from email to PowerPoint to videos.
I have successfully used two inexpensive tools to make and tell others about my team's decisions:
Together, they make a dynamite decision package.
My information mapping software, MindManager, lets me quickly and graphically organize the pros and cons of any problem or issue. Below is a sample I made to help me discover new things I can do with ZoomAlbum. Each section of the map will print to a page in a ZoomAlbum I print. (Click to enlarge.)
You can also see a wireless proposal I made using ZoomAlbum here.