Passed 640-811 ICND exam today with an 875. This was my second try. First attempt, I was rushed for time. You only get 60 minutes, so you really have to watch it. I had 1 simulator.
What I used to study:
-5 day ICND coarse at New Horizons (ok class...but mine wasn't worth 2500 bucks. good thing my employer picked up the tab)
-CCNA exam guide by Wendall Odem
-Network Visualizer 4.0 sim software (do not waste your money on this.)
-and rack time fromChris has great prices on rack rental. 10 bucks for 24hrs. You also get a complete lab book to use along with his racks. His site has a lot of other free study items also. check it out.