Service Stack for services and serves up XML, JSON etc. Amazing in general for setting up the services. Also cross platform.

As far as 'DB communication', if you are able to use Windows Server for hosting, Entity Framework works well, however is code gen but very easy to use and code against. There might be alternatives like DbLinq (Linq To SQL for Mono), but haven't tried it so not sure on how easy it is to use.

Obviously, this is only really an option if you don't mind coding all this in C# and doesn't take care of all the database design you'll have to do, but that kinda goes with game logic.