Business Chinese Correspondence

Does anyone know of a good resource for Chinese business correspondence?  Specifically, I'm mostly interested in e-mail etiquette.  In replies to my e-mails, I seem to get a lot of "看到你的来信很高兴“ openings and "祝你顺利“ closings, along with wishes for my good health.  I don't feel comfortable simply aping these phrases and was looking for a guide to what is appropriate, levels of formality, etc.

Anyway, any ideas would be appreciated.