Has anyone used and can(not) recommend any proof-reading service? I found some on the Internet but have no idea how to find out whether they are reliable or not;(

I paid an experienced proof-reader to correct my Master thesis. I am not from the UK so I didn’t feel very confident about my linguistic skills. However, I wouldn’t recommend the service simply because it is not worth the money. The proof reader only corrected punctuation and did very minor editing. Had I given my thesis to one of my UK friends, the results would have been the same.

Very good question, Verdy!
I have never had anyone proof-read any of my work (yet), but I probably will. However, not a 'professional' proof-reader. I proof-read one of my supervisor's publications, and I made sure that I knew what she wanted from me as a proof-reader. I know the discipline so it made sense - I think this is key!!

When you're getting people to proof-read academic work they need to know what they're reading. My advice would be to ask a fellow PhD in a related area and pay them accordingly. This is what I will do, then they won't correct what they think are mistakes!