I am using blogengine.net blog but I want to migrate it to a SharePoint 2010 foundation blog. Is there any way to make it automatically? Is there a such tool to help me?
These companies produce software to help with migration.
(Not affiliated with and never used any of them)
None specifically mention blogengine.net but I believe that they can all work with misc 'websites'
Most of them offer white papers giving tips on what to look out for when doing a migration.
If none of them fit the bill then you could 'roll your own' solution using SharePoints Content Migration API.
Finally - unless you have thousands of pages it may be more cost effective doing this manually, be pragmatic about it.