I didn't study too much for the NLN. I only had about 10 days to study. I used the book published by the NLN, "RN Pre-Entrance Exam". It was very helpful. I just kept taking the practice tests over and over.
The program now is 6 quarters, we started in the summer and will graduate next December. It is a full time program, so expect to be in either class, lab or clinicals every day, then add study time, and you pretty much live and breathe nursing.
It looks like you will be trying to get the non-nursing requirements done and that's the best advice I can give you. It will make your life a little less stressful if you can just focus on the nursing courses. If you do decide to exempt out of PSY2103, I used the book for the course to study (they have it in the library that you can check out). Do not use the clep exam book. There were some students in our class that used the clep book to study for the test and it didn't help them at all and they didn't pass it. The exemption exam is NOT a clep test, it is a test from the course itself, looked to me like it may have been a final exam, so you really need to be studying from the book they use in the course.
I hope this answers your questions. If you have anything further you want to know, I'd be happy to help.
ETA: I also wanted to add that you want to make sure you study all portions of the NLN review book. My test had a lot of physics on it, but a friend said she hardly had any physics on her test, mostly biology. Just a little tip.