Here is a site endorsed by Microsoft.
http://www.measureup.com/site/microsoft.aspor
http://www.selftestsoftware.com/shop/xt_ref.asp?ref=ms_ptpStay away from BrainDumps. They are not legal. If you feel confident after taking the practise exams, set you exam date. Make a plan. Stick to it. Finish the race.
MCSA, MCTS, MCITP, MCDST, MCP, A+, Network+
Tim