I took the Net+ and Sec+ 3 years ago, then renewed them both by taking Sec+ again in May. In my experience Glen Clarke's study guides were full coverage. I just pulled my Net+ book off the shelf and it's nearly 900 pages. I had no practical networking experience when I took Net+. I had made network cables and physically plugged them in, that was the extent of it.
I am currently studying for my Network+ exam. I am using this book for my studies:
The nice thing about this book is that it comes with a CD that has almost 600 test prep questions along with a lab manual and a bunch of extras. Its not too expensive and I think it is definitely worth the money.
Looking to take my exam later this month and I feel like this book and its resources have been really helpful.