Drupal and georeferencing

Hi,

can you give me some tips to help to solve my issue?

I must make a website with geo-referenced content. The idea is building a website with contents like this http://www.parcoalcantara.it/mappa.php or this http://www.parks.it/riserva.tsatelet/iti_dettaglio.php?id_iti=3300 .

Also I would like to add POI and the possibility to download this POI for GPX, KML\KMZ (Google Earth), etc ..

Can you give me some tips to do this? ie: modules to use and some resources to read (How to, tutorials, article, ....)

Or have you some other ideas to suggest?

Any idea is very appreciated.

Thank you in advance.

gp