All I can say is - relax! The best thing parents can do for their children is to find out their learning style. Once they know that, the curriculum and resource choice can really be narrowed down. If a child is a kinesthetic learner, the parents don't need to focus so much on looking for workbooks but on active learning methods and resources.
I have included quite a few tips on my post about homeschool catalogs that will hopefully help parents wade through all the options and help them make some informed decisions. I hope this post will help relieve some of the stress and give parents lots of good information and links to the best places to look for the resources they need.