I can't speak for law, but you should definitely get the prescribed accounting textbook (for both 1000 and 1030 if you do it second sem). Don't bother with the recommended ones straight away unless you are struggling. Micro its not quite as essential, but still good to get. When I did it sem 1 last year we had a weekly online test worth 1% each (lol) before the lectures for that topic. So the idea was to read up on the topic first and then go to the lecture. You'll find out early in the semester if that's still going on. No textbook necessary at all for etc1000.
But you can wait until the first week or two before you buy the books. So no need to rush out and buy them now.