Hi everybody.
I hope this thread won't be off-topic; I just choosed this section, because the infos I need are still quite general. For further (and more specific) questions, I will open new threads in appropriate sections.

I'm creating a webpage with an online service, which should let visitors to explore a map full (ideally) of resellers with certified green products. Each visitors should be able to: add new markers with specs (address, phone number, etc...), integrate existing markers with new informations and/or comment them.

By now I succeded doing this:
http://www.laboratoriolinfa.com/arpa...ivenditori.php
(sorry, the website is Italian only, but it is just to give the idea)

At the moment anyone can add markers. When you click "save", a MySQL database is updated, via php files. The javascript for the GoogleMap reads from the database (via a php generating an XML), and publishes the map with stored markers. To do this I followed several tutorials and, since I'm still a novice, I understood just partially what I did.

Now I need to add the new features and I would ask if anyone nows websites, with tutorials and/or guides which let to do the followings:

1. create a registration and login/logout form (php?), with associated "user" table in Mysql
2. let content's changing with database update (including deleting a marker and the corresponding row in the table's row); such changing opportunities should be available only to registered (and logged) visitors
3. create a "comment" form (I would like to place a link in each marker's info window, which opens dinamically a comment section outside the map, within the same page)
4. Add only a new marker at the time and refresh the page automatically once the markers' "save" button is pressed. I would like only the map being refreshed, without affecting the rest of the page. I would, in addition, to refresh the map keeping it centered where it is at the moment of saving.
5. To create tables in PhpMyAdmin, I'm having some problems to chose the options for the fields (TYPE, COLLATION, ATTRIBUTES, ACTIONS, ...) Is there a comprehensive guide/tutorial which explains what they are and when to use them?

I DON'T WANT YOU TO DO MY JOB, I'm just telling all the features I have to solve. If any of you have suggestion for ANY part of ANY of the above points, please let me know. I can follow tutorial quite well, by myself. I just need some suggestions to find them

Thanks for your attention (and patience, if you read to this point),
Stefano