Sum 2 tables based on key from other table

Dear Friends,

Please help for the select command, as i had tried many times and always can not display the result as what i want.

I am looking for the solution on google but still can not found the right answer to solve the problem.

I have 3 tables :

Table A
ProductID
ProductName
SupplierID

Table B
ProductID
InitialStock

Table C
ProductID
Date
In
Out

1. I want to select all productID from Table A where supplierID='XXX'.

2. Based on list from Step.1 : sum the initialstock from Table B

3. Based on list from Step 1 : Sum (in-out) from Table C where date <'BEGINNING DATE'

4. Based on list from Step 1 : Sum (in) and sum(out) from Table C where date between 'BEGINNING DATE' and 'ENDING DATE'

So the result will look like this :

ProductID ProductName SumofIntialStock sum(in-Out)<beginningdate SumofIN SumofOut
xxxx xxxxxxxxxxxxx 99 99 99 99
xxxx xxxxxxxxxxxxx 99 99 99 99
xxxx xxxxxxxxxxxxx 99 99 99 99
xxxx xxxxxxxxxxxxx 99 99 99 99

What command to get result like this ? i have tried crosstab function but not success too :(

Thanks in advance