New Post: Grouping sources in the bibliography

1) Yes (and no). It is possible to group them, by providing the 'SourceType' as the first part of the sortkey. This will nicely list all your sources according to their type. However, when finished, you will have to convert the bibliography to static text and add the different titles (Literature, Internet References, ...) yourself.

2) Use a column based format. Using whitespaces / tabulators will never get you perfect alignment, tables will. The IEEE style uses this if you are looking for an example.