I've heard Fitday.com can give you pretty good estimates, as well as WebMD. I would go with either one of those over FatSecret because it tends to overstate calorie burn. If you're just starting out this should be close enough, just keep in mind that nothing is going to be exact.
Personally as I got further into my journey I wanted a more accurate way to measure what I burn through activity, so I invested in a Bodymedia Fit activity monitor. Google it to get more info, & you should also search the forums here for it, I wrote a review after wearing it for a week. If you've ever heard of the BodyBugg, it's made by the same company. I LOVE mine.
| NO EXCUSES, JUST RESULTS
| Next milestone - 256: 60 lbs lost2013:
still up from 1/1, but coming back down...2010:
50.4 lbs lost | 2011:
17 lbs lost | 2012:
1 lb gained
How I did it: http://stubbysticks.wordpress.com/weight-loss-summary-by-month/