As a non-native speaker of English, it can often be hard to spot some of the errors that a native speaker would find. For a long time, I've been thinking about getting a native speaker to help me with proof-reading my texts (articles, theses, application, etc), but I don't quite know where to look. What are some good ways to get proofreading for your texts?
For example, are there any websites on the Internet where one can exchange proofreading services between different languages? (Say, if you help me proofread my text in language x, I'll help you with yours in language y.)