SO much shopping help, I need!

Is there such a thing as a decent-sized (ie can hold a paperback book along with plenty of other small shlock) shoulder bag that also has compartments so that everything in it doesn't fall straight to the bottom? In my experience, I can either have a smallish bag with compartments, or a big bag without compartments. I want the best of both worlds!

While I'm here, thank you SO MUCH to everyone who offered advice re: beach towels and bras. I haven't actually done anything yet, but I will, and I'll report back!

ETA - justhuman?! Can you remind me where your bag came from again?