Constructing a good customer survey

Question

What questions can I ask and what other considerations are important to make this survey effective, so that people actually fill it out?

I will be distributing it only to existing customers of my small e-product, to collect testimonials and other general information from my customer base. I plan on using Google Docs to conduct the survey, but was wondering if someone has some good advice on questions that I can use. I have planned a couple:

1. How would you rate X on... Features, Usability, Support, Pricing?
2. What do you love/hate about X?
3. What features would you like to see in X?
4. Would you like to share a testimonial with us?

Also, should I be breaking it into multiple sections/multiple pages? (Google Docs has that option.)

Answer 1

Check these 12 tips Zoomerang has for making better online surveys there are several in there I never thought of. Try it: http://snurl.com/12surveytips