I would like to recommend your this fabulous navigator in order to improve your English and avoid from having spelling mistakes, not only for using this blog but also to sent post to our webct forum.
The first tool I would like to introduce you is the new spell checker you could find in the new Firefox version: http://www.mozilla-europe.org/en/products/firefox/
Thanks to it, everything you write, either in English or Spanish, could be checked while you are writing. You could also add new words to the default list of words.
The other option, not new by the way, is the possibility that Firefox (and now Explorer 7) has to add quick search buttons to the most famous and useful dictionaries (Open Dictionary, Merriam-Webster, DRAE...)
Just click here and write "dictionary" or anything you would like to find.