Dot net framework
Data import wizard
Prompt Softech has suggested a Nonprofit success pack application from app exchange to manage all the Accounts and journal entries from eTap into salesforce platform.
Also for migration a complete eTapestry and Salesforce integration solution Via API Dot net integration to fulfil and provide an end to end Consulting, Migration , and Support.
Apart from API integration Prompt Softech has also suggested to build query in eTap and create reports for the Accounts and Journal entries and import the data in NPSP data imports object in salesforce.