You can't read the transaction log file easily because that's not properly documented. There are basically two ways to do this. Using undocumented or semi-documented database functions or using third-party tools.
Note: This only makes sense if your database is in full recovery mode.
SQL Functions:
DBCC LOG and fn_dblog - more details here and here.
Third-party tools:
Toad for SQL Server and ApexSQL Log.
You can also check out several other topics where this was discussed: