Looking for special english courses

Alright guys I have quite a dilemma, I have been in business for a long time, I give lectures and even write few articles. While I have a strong capacity to express myself I make a lot of grammar mistakes , I twist me words, and I spell like a 10 year old (thank g-d for spell check). I might lack some vocabulary once in a blue moon but that should not be a big deal. The biggest deal is the grammar. Just last month, me and my friend were laughing at someone on T.V. that used the word "intelligency" and then my friend turned to me and said" you know what, sometimes you make this type of mistakes also" He was right, and I simply don't want to think about how many times I have embarrassed myself without even knowing. I can tell you that unless I read an email 5 times over and over and then passing it by my secretary to proof read, I usually end up with many mistakes. Actually my quick emails have been subject of ridicule for years. So I realize it's simply time for a change. I know that I have a slight learning disability. I was not confirmed if its dyslexia or something else and I never done the for a full test. Then again, it simply doesn't matter, because it has been an excuse of mine for too long.
My major dilemma is not whether I should be taking courses but what course I should be taking. I'm clearly not a beginner, but some of the mistakes do belong in a beginner course. The truth is I don't think that I need a simple course that teaches me straight forward vocabulary and grammar. I need a course that reprogram me out of bad habits and force me to use proper English. Maybe forces me to simply pay attention while I write and communicate the first time. Like one of those Golf courses for advance players ?

Hope someone can suggest me or maybe other solutions