Welcome to the forums Marcio!
As Edhy said, you'll typically need to create fill methods (see the help file) to load the BO. There are a few that are built in that are pretty handy.
- FillByPrimaryKey: fill BO with a single record, using the PK of the table.
- FillByParentPrimaryKey: fill BO with records matching a FK to a parent table (think fill orders for a single customer).
- FillDataTable: This is what you'll use to build your own.
Here is one I use in test apps a lot, just to load some data into a BO for some other test I'm doing. This goes into the BO code file.
/// <summary>
/// Fill the BO with the indicated number of records. This is 
/// generic enough to use with any BO. 
/// </summary>
public void FillTopN(int n)
{
    //-- Build SQL Statement.
    StringBuilder sqlBuilder = new StringBuilder();
    sqlBuilder.AppendFormat("Select Top {0} *\n", n);
    sqlBuilder.AppendFormat("From {0}", this.TableName);
    //-- Load data.
    using (SqlCommand cmd = new SqlCommand())
    {
         cmd.CommandText = sqlBuilder.ToString();
         this.FillDataTable(cmd);
    }
}
Let us know if you run into any problems.