Can anyone recommend a good dehydrator for drying herbs and lavender? Also, can you use your oven for drying?

We have some great growth this year and there's no way I'll be able to use it before the frost. We have basil, dill, cilantro, oregano, lavender and some others. This is our first garden, and I'd like to keep the herbs for the winter. Can anyone recommend a good dehydrator (perferably one you've used personally)? Also, can you use your oven to dry herbs? And finally, are dried herbs more or less potent than fresh. Thanks! =)