Here are some of the tools that I use:

1. Cantonese Romanization

The best thing I ever did was to learn a Cantonese romanization system. I learned Yale at the Chinese University of Hong Kong and have been using it extensively ever since. Another option is Jyutping. It doesn't matter which method you choose, but learning a romanization system will help tremendously if you are serious about learning Cantonese:

Yale: en.wikipedia.org/wiki/Yale_Romanization

(see also: www.cantonese.sheik.co.uk/essays/jyutping.htm)

2. Yale Input

You will need to use additional tools in order to input Yale because it uses diacritics as tone markers. I use the following on-line tool to generate my Yale text. It is fast and accurate. Select Yale (tone numbers) to Yale (original):

www.kodensha.jp/webapp/cantonese/can_converter_e.html

3. DimSum Chinese Tools

Romanization systems are great, but sooner or later you will need to start learning, or at least using, Chinese characters. Romanization systems are 100% phonetic; once you learn a system like Yale you should be able to read Cantonese ping yam with close to perfect pronunciation. However, with ping yam, the meaning is ambiguous as Cantonese reuses many sounds. The following tool is great for looking up Chinese characters, their meaning, as well as their Cantonese (and Mandarin) pronunciation. You can look up words based on writing the character or using ping yam:

www.mandarintools.com/dimsum.html

4. SitePal Text-to-Speech

Since I am able to speak Cantonese but not able to read Chinese very well, I rely on spoken Cantonese for communication. If someone sends me a message in Chinese it will take a long time for me to translate it word for word on my own. One of the first things I do is copy the Chinese characters into this tool so I can hear them being spoken in Cantonese. This gives me a quick way to start thinking about and deciphering the message:

www.oddcast.com/home/demos/tts/tts_example.php?sitepal

5. Google Input Tools

I use Chrome as my web browser, and Google has a great intput tool for entering many different languages. This is one way I am able to input Chinese characters. Search for "google input tools" in the Chrome web store at the following link and install Google Input Methods (by Google):

chrome.google.com/webstore/category/apps

6. Google Translate

The Google translation engine is a great tool for converting from Chinese to English and vice versa:

translate.google.com