When I started going to the gym early, before work, getting out of bed at 6am was the hardest part. What helped me transition to being a morning person was to buy one of these: http://www.amazon.com/BioBrite-Sunrise-Clock-Radio-Platinum/...

It's a much more pleasant way to wake up in the morning, as it mirrors nature. I've found that after using it consistently for about a week, my sleep cycle stabilizes on the schedule I want, and I can usually get up naturally when I need to and beat my back-up buzzing alarm.