I sat for the CCENT this previous Friday and passed with 24 minutes to spare!
I'm not a networking guy and have had very little real life exposure to Cisco equipment (I'm hoping to change that :)). Here's what I did to prepare in case there are others in my position.
I watched the CCENT course here all the way through from start to finish and made sure to watch some every day until I was done. I use a program called MySpeed and upped the playback to 1.8x. Don and Ronnie sound stoned now at normal playback speed.
I created a free account at subnetting.net and practiced the subnetting questions for probably a total of 5 - 7 hours, again making sure to do at least a few everyday.
After going through the measureup.com practice exam a few times I went back and re-watched the entire course again. This time I paused and took notes and made sure to write down every command that Don and Ronnie used.
After reading tons of positive reviews I purchased the practice exam from boson.com. I ran through the randomized practice exams multiple times, reviewing and taking notes on the questions I got wrong. ITPro.tv and Boson would be a match made in heaven
The best advice I can give is study OSPF and its various show commands and practice subnetting until you can do it in your sleep.
Thanks to Don, Ronnie, and everyone behind the scenes!