#1- I buy for the whole family, so we tend to split things. We don't use herbs a lot, we use a lot more dried chiles. What I do have is theme weeks. Sometimes I'm just in the mood to use a certain vegetable. I'll plan a week for bell peppers, broccoli, etc.
#2- it happens, but I try to avoid it as much as possible. I use the weekly circular that comes to the house on Wednesday, for grocery shopping on Saturday. Sometimes my nose gets the best of me. Strawberries have been really fragrant lately and they've been a really sweet snack the for last week.
#3- foodnetwork.com or allrecipes.com. I havent been following through with actual cooking since my mom isn't to keen on sharing her kitchen with me.