There is already a setting to save the insert id into the session in the user interface. Just make sure the inserts are applied in the correct order on the page and the session variable will be available.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.