Dear Chris,
Have you found the English-speaking teacher to help you with your writing? If no, try this website
http://www.taiwan-taipei.com/index.html, a communication platform for westerners in Taiwan looking for teaching jobs and exchanging info.If you've found one, please discard this reply.
Be aware that not all western English teachers listed there are native speakers, nor do they all have a degree in TESOL or TEFL. It depends on your needs and the context you wish to improve your writing. Say, for example, if your intent is to improve writing for academic purposes, then looking for a qualified native speaker armed with the right eduation background and experience would be your best bet. If you write for work, then native speakers with good years of work experience outweigh their academic quali. Or, if you just wish to improve your general writing skills, not really for work or for school, then any westerner would do as long as you like his or her writing style.
Having said that, you may also want to consider another factor--explanation of the writing problems. Often time you'll find a qualified proofreader or editor willing to revise your writing for a fee, but the fee usually doesn't encourage them to explain or point out in detail the reasons for the changes they make to your writing. All you will see is their corrections on your returned writing. Is this a factor to you? If yes, see if you can find native speakers who can either speak Chinese or support you more than just correcting your stuff.
No doubt, writing, especially guided writing, will boost your written communication skills.
Hoping this information helps. If not, let me know how I can better help.
chister