In your specific case, I would suggest you get a list of September's courses, visit each professor, and ask for the title of the book they plan to use. Then buy it, and read it at a comfortable pace over the summer.
The college library may have older editions available for loan, too.
In a general case, I'd recommend the "ARRL Handbook for Radio Amateurs". It has 80 to 90% of the material you'd cover in 3 years at college, all condensed into one book, is easy to read, includes projects and theory, and costs only $40.