I'd also recommend you take a look through "SQL Server Transaction Log Management" by Tony Davis and Gail Shaw.

You can obtain an electronic copy of the book from this site: http://www.sqlservercentral.com/articles/books/94938/

There's also a SQLServerCentral stairway on the topic: http://www.sqlservercentral.com/stairway/73776/

Together, that should provide you with everything you ever wanted to know about managing the SQL Server transaction log.