i know it's been a few months since you ask these questions and might have even gotten the answers by now..but i will answer them anyway and hope it helps you...

1. I personally do very little shopping at health food stores or my local markets... we are blessed to have farmer's markets around here and i get as much organic as possible...if u do not have that luxury, then you want to check around or online for an organic co-op to buys produce at a reduced costs as compared to the stores...items to purchase: organic produce of any sort, virgin coconut oil (although tropicaltraditions.com is great to order) virgin oil and sesame oils, hemp seeds, chia on occasion, nutritional yeast, nuts, seeds, phyllium husks (to thicken items), buckwheat and wheatgrass seeds for sprouting and growing and such...that's about it for me...of course, spices...

2.as much as possible that is organic...avos that are not organic cuz they are low on the pesticide spray list...
3. wheatgrass for juicing and mung, lentil, fenugreek, buckwheat sprouts...some herbs...looking to do more once we get our yard set up :)
4. YES...lots of sites..just google serach and you will find just about anything u need
5/my hubby and I spend about $60 a week on average...not bad for two people, eh? clean healthy food? we don't eat out much and make our foods...and have our dehydrator for snacks...

enjoy your journey...it is a marvelous one!!...blessings...