IMHO, it's VERY important that your read the book before you start. The GFGCG is helpful, but it doesn't tell you which Phases allow which foods. If you make your shopping list using it, you'll be very confused and very unsatisfied, I think.
Instead, get a copy of the book (you can borrow one from your library if you can't afford a copy right now) and read it. You really need to understand the reasons for what we do so that you can make your own educated decisions about things in the future that aren't mentioned anywhere. (Like, "Why can I have stoned wheat crackers, which have enriched flour, but not Triscuits, which are made with whole wheat flour and no SBD-offensive ingredients?"). When you've read the book, check out our FAQ here for the updated lists of foods to enjoy/avoid as they change regularly as Dr. A learns new things about scientific studies involving food.
Glad to have you with us! I hear you about lunches...both my husband and I enjoy bringing leftover dinners with us for lunch. A hot lunch just seems more satisfying. Do you have access to a microwave at lunchtime? If so, I'd just make extra for dinner and package a serving away in a microwave dish (like CorningWare's Pop-ins with the pop lid, or the one made by Tupperware) and take them to work along with some veggies and dip or bell peppers and hummus, etc. Don't forget to pack snacks, too!