http://www.professormesser.com/ is a free, online website that has many videos for both the A+ and Network + exams.
Over at the CompTIA website, Network + objectives:
http://certification.comptia.org/getCertified/certifications/network.aspx Finally, Amazon has CompTIA Network+ Certification All-in-One Exam Guide, 5th Edition by Mike Meyers for only around $30 here:
I highly recommend both Professor Messer's website and the book, and with both you should be able to mark off the exam objectives with relative ease from just these two sources.
Another suggestion is to head on over to your local library and ask that they buy a copy of Network +, or perhaps they even have several sources of Network + available. As far as I understand it, the Network + exam hasn't been updated in awhile, so a potential library may have Network + material close to or exactly related to the current exams.
Best of luck.