I guess that if you didn't choose one of the numerous library available, you want to do it yourself.
So, XML is simple text
For a single address, the XML file will look like:
="1.0"="utf-8"
<adress>
<name>My Name</name>
<street>My Street</street>
<city zip="My Zipcode">My City</city>
<state>My State</state>
</adress>
for a list of addresses:
<pre lang="xml"><?xml version="1.0" encoding="utf-8" ?>
<list>
<adress>
<name>My Name</name>
<street>My Street</street>
<city zip="My Zipcode">My City</city>
<state>My State</state>
</adress>
<adress>
<name>My Name</name>
<street>My Street</street>
<city zip="My Zipcode">My City</city>
<state>My State</state>
</adress>
</list>
</pre>
Simple!