How to draw a map of postal codes of a country?

Question

I have data:

postal codevalue
00-002          50      
00-003          70      
...
99-440          510    

where postal code is a postal code in Poland, and value is a number (it can be number of people, density, temperature etc.).
I want to create a map for this data. So I need a map with areas coloured depending of a value. Something like this here. So such data exists somewhere.

• How can I get data that I can use to draw the map of Poland divided into areas with their postal code? Where can I find it?
  
• What software can I use to do this?
  
• If this is not a proper place for such question, where can I ask?

Answer 1

1. To create a map like that, you will need a country boundary map, a state boundary map. I believe you can find the data you want here. Try to search within the website.

   If you are looking for more gis data of Poland or other countries, try to find them from institutional sites. Sometimes you need to request them by sending email to a certain organization. But the easiest way to search data is google key words.I did this by google "gis data Poland".

2. Because data above is in shapefile format, I would recommend you to use gis software that support this kind of format. QGIS and ArcGIS are both good choices. QGIS is a cross-platform free and open-source desktop GIS application that provides data viewing, editing, and analysis capabilities. ArcGIS costs you thousand bucks to buy license. But most educational institutions have bought it for students to use.

3. Once you have access the data, try to open it and see what is in attribute table. If you don't know how to do, go to Youtube to see some tutorial videos (QGIS,ArcGIS).