Dynamic Pivot Table (Partition) Creation

I have 2 tables , which can be mapped with a common column and the second table's rest of the columns should become like columns(like pivot) and in the second table itself 1 more column called value , this sum of the value becomes a value to the pivot column value. For this I am using CASE structure and I am writing the individual case for each column , but I am sure after some extent case don't work at all and I would like to do it dynamically( when ever the new entry will come into the source table , my proc has to pick automatically the new value and put the new value as part of pivot structure) , so pls share your inputs and if possible provide some sample code.