Check out the Campaign for Plain English’s site and especially:
Also, check out Jakob Neilsen’s articles about writing for the web. In particular:
If you work with websites or user interfaces, pretty much anything Nielsen has to say is worth reading.
There are some useful articles on this site too:
- How to write great case studies
- Being human is overrated (but not when you are writing)
- Bad reader, naughty reader
- Economist style and business writing
- Geeks: how to write for a non-technical audience
- Seven types of bad writing
And as a special treat for lovers of bad marketing language and daft naming conventions, please read this short piece from the New Yorker: The Privileged Few. It made me laugh until I cried.