This is for those attending future TT's at the locale!
There is a Ralphs and a Rite Aid really really close. Shuttle is supposed to be up and running starting this weekend, but really it's just across the street so it's no big deal to walk. These 2 are VERY well stocked with just about anything you can think of which will make packing easy regardless of where you come from.
Ralphs not only has a fair selection of fresh fruits, vegetables and juices they also have a fair selection of pre-made foods. They have a pretty okay selection of foods also. Yes, if you need Spanish Almonds picked by blind monks on a full moon then you'll have to bring your own, but is common almonds will suffice you'll be okay ;) The Rite Aid has more stationary supplies (journals, notebooks, pens, pencils, etc) than you could ever wish for. Again, if you insist on a Moleskin or specific pen brand you may want to bring your own. They have TONs of first aid supplies, hygiene products, ear plugs (if you forget this and your room mate snores you'll regret it day 1. In addition the movies are DEAFENINGLY loud so I put my ear plugs in and i can hear everything clearly (the added bonus is you block out the people blabbering constantly during the movie). The Rite Aid has an impressive selection of sun block but it does only carry the SPF30 Blue Lizard sport (if you have no idea why I mention this you can tan and thus are not subject to the nuances of the finer sunblocks ;) ) Hair supplies vary from Pantene to Paul Mitchell, so the selection is better than we would expect. Heck they have Matrix, Biolage, Nizoral, Fekkai, Redken, you name it, so no problems there. Neither with hair, nail and face accouterments. Water bottles may leave some to be desired for most. The selection of protein bars and Protein powders (and similar delicacies) nearby is very limited (half a smidge above non existent).
The hotel itself has several shops where one could buy clothing, swim suits, cover ups, shoes, one (actually a good brand) of protein bar, spa essentials, and a handful of first aid supplies (nice to be able to get mootie when needed!)
In short, day to day supplies can be gotten across the street at any time; with certain other essentials being on hand on-site.