Translation:A good Esperanto speaker has large dictionaries.
This is so indisputable. Whenever I learn a new word in Esperanto, the first thing that I do is go to http://www.esperanto-chicago.org/rootsglossary.htm or some other root word glossary. From there, I use Control + F (or Command + F on my Macs) for the individual roots of the new word that I have learned. This allows me to track what the roots within the word mean and how they change the meaning of the word.
I use the text Esperanto English dictionary from http://www.denisowski.org/Esperanto/espdic_readme.htm. Wrote a Python script to convert it to an sqlite db and search it. Thinking about turning it into a web interface so you can click words in the definition and see their translation. This is a pretty good dictionary.
This looks pretty useful. A web interface would definitely make an excellent addition to compliment the Python script. ;)