I have postcode level data in an Excel workbook and ideally I would like to have a map on another sheet of the area that I am interested in. The postcodes in my dataset should be highlighted within that map. I am using Excel 2010 and have no prior experience with GIS but plenty of experience with C#, Java. Any ideas of how I can achieve this? I looked for open source add-ins and didn't find an awful lot. Is there another way I can achieve what I want?
I use Topo.ly. You can just copy all your post codes from Excel and paste them in Topo.ly, and it will plot them on Google Maps. It also hosts your maps, so you can save it and come back to it later, or share it with others.