Module development and code questions

I would like to know if there is a module that can read from a database a reference address along with one or more desired addresses, and determine if those addresses are within a specified radius (KM/Miles) of each other; in addition, can this module provide driving directions and the distance from the reference address to the found desired addressess?

I'm trying to implement the user hook in a module. everything works fine, except that it doesn't redirect properly- doesn't login upon immediate login and gives message when not- drupal just returns to the /user/register page.

here's the code:

I have a 'sitemap' menu item on site I'm developing. This menu item leads to a page that should have a UL-list of items available to any user. I guess I need a module that would generate this page according to a menu of the site.
Is there such a module?

I developed a custom module that provides customer news nodes. These news nodes have a set of new fields (so standard node has to be extended) and sophisticated visual appearance, so I had no other choice other than to come up with custom module in case you interested. Time was good.

I understand that these are for translation, but why do certain modules need to contain their own? or is it simply because the phrases are to specific?

Okay, been working on a new module as a learning the drupal api exercise and I am finally down to only one problem, I think.

I'm using xampp v1.6.3a with php 5.2.3 and mysql 5.0.45... I'm using firefox 2.0. Below is a copy of the module code that I am using as my learning experience.

The problem currently is that every time a form of any kind, anywhere on the test site is submitted I get the White Screen of Death, I put my cursor in the address bar of the browser and hit return to load the page and it'll come up fine as it should (or at least as one would expect). If I disable the module, everything works like it should. Re-enable the module, broken again.

This can't possibly be a memory problem as I put the memory allocation on my test server up to 512MB...

Now, for some trouble shooting steps I have already taken:

1) I put the module up on a production site to see if it was someone linked to server conf, no luck. Same issue, but I do actually get an error on the production site, however I'm not sure it's relevant to the problem as I have output buffering turned on on my test server.

warning: Cannot modify header information - headers already sent by (output started at /home/crimson/public_html/sites/all/modules/idkfa/idkfa.module:1) in /home/crimson/public_html/includes/common.inc on line 309.