We have had no experiences with integrating Sitefinity and aspdotnet store front. What I can tell you is that Sitefinity has a fully exposed API, is built on provider model and is a native ASP.NET application. If the same is provided by aspdotnet store front you should be able to integrate them fairly decently.
I am sorry that we cannot help you more, but do let us know if you have any more specific questions.
the Telerik team