Currently Inventory and Accounts are not linked. In the future I believe this is something @emre is looking to improve.
There is a way to somewhat do this which @qmckay has done with a very elaborate and complex php/sql solution of his own design. This is a complex setup requiring a web server and php installed to run. I doubt @qmckay will provide much more support for it if you do not understand it as it requires knowledge of php, web servers, and sql.