Google refine does not offer a native way to add rows in a project. As said in the discussion list, the purpose of google refine is not to be a spreadsheet editor and should not be consider for records creation but more analysis and mass edit.
The best way to add some rows to a project is to export it and add rows in a spreadsheet editor (Excel or OpenOffice Calc).
However here is a quick and dirty trick to add few rows at a specific location in your project.
1. Create a blank column based on any column in your project.
2. Add manually text (that can be anything) in all the cells
3. Transpose this column by ignoring blank rows and not prepend the column name
4. Here you go! You have a new blank row in your project, now you can edit it manually of fill it down!
The best way to add some rows to a project is to export it and add rows in a spreadsheet editor (Excel or OpenOffice Calc).
However here is a quick and dirty trick to add few rows at a specific location in your project.
1. Create a blank column based on any column in your project.
2. Add manually text (that can be anything) in all the cells
3. Transpose this column by ignoring blank rows and not prepend the column name
4. Here you go! You have a new blank row in your project, now you can edit it manually of fill it down!