Double-click the tabulizer application, or type cmd-N within tabulizer, to create a table. The default column headings are probably not what you want to use, so click the "Edit Columns" button (cmd-/ for short) to display the components for changing the number and names of the columns (screenshot below).
You can double-click on any column name in the drawer and type a new name for the column. The tab key moves from one column name to the next. The two buttons allow you to create a new column (on the right side of the table) or get rid of the rightmost column. When you are done editing the columns, click the button or press cmd-/ again to hide the drawer.
To add a new row to your table, simply press return. You can then start typing into the cells of the row, moving from one cell to the next by the tab key. You can also go back and edit any of your old data by double clicking on it and using the standard Mac OS editing commands. When you are done adding data, use the Save command (cmd-S) to store your table to a file.
Clicking on any column header will sort the rows of the table by the values in that column. Clicking again on the same header will toggle between ascending and descending sorted order. If you wish to rearrange the rows in some unsorted order, you can select some rows, and cut them and paste them into the desired position. You can also rearrange the columns by clicking and dragging them, and change the widths of the columns by dragging the boundaries between the column headers.
If you remember some text which occurs in the row, you can use the Find command (keyboard shortcut command-F). This will open a dialog which will ask you for some text to search for, and where to look for that text in each row. By default, it will find the first matching line in the whole table, but there are options for other search patterns such as starting from the currently selected line and finding the next match. Once you have already done a search, you can use the command-G (search again forwards) and command-D (search again backwards) commands to move around to other matching lines.
The easiest way to exchange data with another program is by copy and paste. Tabulizer's copy and paste operations can handle data in a Mac-standard tab-separated value format; we expect this to work with other spreadsheet programs, but have not yet tested this. In addition, tabulizer can also copy its tables into plain text strings (suitable for pasting into text editors such as BBEdit), and HTML-formatted tables (suitable for pasting into TextEdit; note, however, that TextEdit lacks the ability to edit or format such tables once they are pasted). Tabulizer's data files are in standard XML format, which can be read by many browsers and XML editors, but can not likely be read by spreadsheets or text editors. We intend to add options to tabulizer's routines for reading and saving files, to handle standard spreadsheet formats such as csv or tsv, but this is not possible yet.
All operations that change the table can be undone by the Undo command (cmd-Z). Continued use of Undo will back up through the history of operations until the most recent file open or new table command. To perform an undone operation again, use Redo (cmd-shift-Z). You can also use the Revert command to return to the most recently saved version of the file.