For your first question, I think the easiest way is to let Excel access you db directly. Search the web for excel and odbc. In excel 2007 take a look at get external data under the data ribbon.
For your second question, I'm not sure which service you want to use, but e.g. messaging can be connected to JMS. ActiveMQ is a JMS provider that can be accessed easily from all kinds of clients (eg java, php, c# etc etc). I think other services should be possible as well.
Maybe if you ask more specific questions, someone will be able to give you a more specific answer.