I’m not clear on what you are asking, but I’ll do my best here.
If you are trying to convert the SQL Server Transaction Log into a text file, you don’t. There are a couple of applications you can use to view the data in the log file.
If you have a text file you want to import into a SQL Server table, you do this using DTS (for SQL 7 or 2000), SSIS (for SQL 2005 and higher), BCP (all versions) or the BULK INSERT T/SQL statement (all versions).
Each of these techniques has a different process. I’d recommend that you use the BULK INSERT statement if possible as it is the easiest way to put the import in the middle of other processes. BCP and BULK INSERT are fully documented in books online.