I use
http://dictionary.reference.com/ often. I just keep it open while I'm online. You can switch to thesaurus.com, translator, etc., from there. Very useful! I will admit that technical jargon is often a problem. Sometimes,
Model Aviation magazine has a page of definitions for our common technical abbreviations. "MA" comes with your AMA membership, and I'd expect you would need membership/insurance if you are to fly at any of the public flying sites in LA, or join any Chartered Club in the area.
There is a "spell check" on this forum, but not many seem to use it. It is not able to correct many English words that sound the same* but are actually spelled different and mean different things, so it's only moderately useful. *Examples: there, their, they're. "Lose" and "loose" are often used improperly here, and Spell Check won't help a lick, because they are correctly spelled, but used wrong.
Best help I can give you is to get with a club in your area. "Knights of the Round Circle" and "Valley Circle Burners" are the only two I know of in LA. Somebody will give you contact information, I'm sure. I'm a long way from there!
Steve