There are many application are available in the internet for the conversion of lotus notes to outlook PST file format. There are two methods are available for the migration of NSF to PST, first method you can convert manually and second is use any third party software. Here I am discuss any third party application. There are many third party tools are available in the market todays but I would suggest you try to use NSF to PST  converter without pay any charges. So If you are interested to download NSF to PST Converter software from the google.