I would like to be able to manually configure the meta tags, keywords and description,for each individual page of the sites. I couldn't find any module out there for drupal 7 that does so. Anyone have heard of such a module? If not how hard would it be to make this a custom module ?
There is a complete rewrite of the old drupal 6 module nodewords in progress now - it is called metatags. However the metatags module looks like it is still in the initial development phase, so you might be better off using http://drupal.org/project/metatags_quick - which already has a stable 7.x release
There is no releases on the project page, but you could clone the git repo and help with the issue queue and submitting patches back etc
As a co-maintainer of the Meta tags module, I personally think it's the best option, but of course I'm biased. We are making great strides to stabilise it; I suggest trying out the latest and letting us know how it works for you.
Disclaimer: I am the maintainer of the Nodewords module.