Hi Anuj,
you may use custom providers even with Free edition. Please see here: http://devnet.kentico.com/docs/devguide/event_handling_overview.htm for more details about configuration of custom handlers.
It handles nodes in the content tree (not e.g. CSS stylesheet). You may add the condition about the document type like on the sample in: http://devnet.kentico.com/docs/devguide/index.html?disk_permissions_problems.htm
// type the document as TreeNode
TreeNode newsDoc = (TreeNode)treeNodeObj;
// handle the event only for news items
if (newsDoc.NodeClassName.ToLower() == "cms.news")
Best regards,
Helena Grulichova