I believe she is either in Portugal or Spain, within the distance that the rental car drove on one the McCann's excursions. Fatima? Huelva? Another village along the way?
The main road near the resort was being dug up and paved over, with holes everywhere. They didn't have to dig a grave. This article has a good map showing which streets were paved over since then, and how close they were to the family's hotel:
http://www.thesun.co.uk/article/0,,2005320001-2007420470,00.html
from the moment this story broke the Mccaans have been under the glare of the worlds media , TV , paparazzi , police , etc etc
Every where they go some journalist usualy follows them with the hope of a good story / picture .
I just cant buy the fact under this sort of scrutiny they could just dispose of a body 25 days later . - at this stage the police probably has their suspicions anyway and would be keeping an eye on things.
anything I suppose is possible in this world - but I just cant buy that theory