You may be wondering just who a web writer writes for, well I can tell you, just about anyone who wants to hire and pay the going rate - providing it is ethical and family friendly I will write it.
Bidding sites and forums are good sources of work, as are recommendations from other writers or writing for someone who has a work overload. I have had all these types of writing over the last two and a half years, I've also written a couple of guest posts for other people's blogs.
I also try to write for a specific audience in my blogs i.e. those interested in writing just like you, and I write research reports for community organisations and universities. Who do you write for?
