Hi Joe,
I would highly recommend reading any and all articles by Joel Smith. Specific to Inventory Solution 7.0, see these:
https://www-secure.symantec.com/connect/articles/introduction-inventory-solution-windows-notification-server-70
https://www-secure.symantec.com/connect/articles/inventory-solution-70-sp2-introduction-and-troubleshooting-guide
https://www-secure.symantec.com/connect/articles/introduction-inventory-solution-windows-notification-server-70-detailed-file-inventory-and-
http://www.symantec.com/community/article/6201/inventory-solution-70-database-schema-part-1-operating-system-inventory
https://www-secure.symantec.com/connect/articles/inventory-solution-70-database-schema-part-2-hardware-inventory
https://www-secure.symantec.com/connect/articles/inventory-solution-70-database-schema-part-3-software-and-user-inventory