Did you check you the learning center on the SCP page? http://www.solarwinds.com/certification/network_certification.aspx
You'll find a sample exam, recommended study areas and hours of training videos to help prepare you for the exam. Successful applicants also generally have 2-3 years of network management experience and at least a year working with SolarWinds products. If you don't have a copy of NPM you can download it here to use for 30 days while you prepare. http://www.solarwinds.com/network-performance-monitor.aspx.
Good luck!