You definitely can, but nothing beats hands on as I have found out from other people that have self-studied as I am doing. This cannot be stressed enough. Interesting as it may be you can get kits comprising most of the equipment you will need to practice for the exam @ some very good prices. Here is a link http://www.ciscokits.com to the place I bought my stuff at, I have since added 2 more routers (2610+1750 and another 2924 switch). Ideally you would want a 2950 switch but the 2924's will be good enough for doing your labs and the CCNA certification.
If you need further assistance with your choices etc, link me up and I will provide you with some additional information links that can help you in your preparation for the CCNA.