My intention is not to advertise the following books/Authors but they are 'standard'...So,if you want to be really prepared beforehand , the recommended basic books to study are:
-mathematics for engineers(amazon website is selling 2 good ones).Imo,prefer math books that include in their title the word 'engineer'.I bought Troba's book only to find it too theoretical,more appropriate for math majors,you need engineering oriented books.
-Sedra Smith's,Malvino's and Boylestad's books about electrical and electronic circuits and devices.Must have them all and fully comprehended.These are your EE Bible...
-Systems and controls books(introductory books not advanced).Systems and controls is time consuming if properly studied,a must know subject beforehand or you might STRUGGLE if the professor is not so good a teacher!Expect HEAVY use of maths...
-All Scaum's outline series books:electromagnetism,electric circuits,analog,digital design,mathematics,physics etc etc.These books are cheap to buy and have a TON of SOLVED problems==> digest them and you can skip some lectures early in the morning!Plus,if you "don't have money" ,you can download them for free via torrents...