api basic tasks

Hi all.
I still need help in using the Gallery2 API.
I need to perform some basic tasks using the API, I'm in a hurry so any help will be welcome.
I was able to:

- get all the images in a given album

Now I need to:

- get a list of all the albums in Gallery
- get the thumbnail of a given image
- build some useful urls, like the thumbnails one, or the images one

Many thanks for the help.
Bye