Thai, Chinese, and Japanese chiles - and any small, thin-skinned, pointed red chiles, really - should just be air-dried, as they are so low in moisture that they shrivel up in just a couple of days. Even in our relatively humid climate, I have never had any mold problems. Higher moisture chiles - even thin-skinned Habaneros - should be done in a dehydrator.
For herbs, I generally just bundle them tightly, and hang upside-down in a well-ventilated area, out of direct sun; store the whole branches in a big zippy bag. This works fine for tarragon, oregano, marjoram, thyme, and sage, as well as lavender, should you have enough flowers on hand to do it. I have a bay laurel, too, and I just leave the individual leaves out on the kitchen counter until dry, and store in a glass jar. Some herbs aren't worth the bother, though, like dill weed, chervil, and basil; they don't have enough essential oils to retain any flavor. Dill seed is another story, though - plus it sprouts like mad after reseeding, as does chervil seed (though chervil seed doesn't have much flavor to speak of).
Good luck, and have fun - it's interesting to see which herbs, spices, and chiles retain their flavors best.