As others have stated, C# is a lot closer to java than C++.
With respect to Web services, which I take to be your focus based on the title and tags of your question, there are two options in .NET, ASMX or WCF.
ASMX web services are the older technology, basically ASP.NET intercepts and processes requests using the ASP.NET stack. These services can be added as a reference in other .NET apps, which generates proxy code to easily access the service. There are also IIS web server extensions that provide security and other functionality. ASMX services have been supplanted by WCF, but are still supported.
WCF is the newer service technology from Microsoft, you can easily configure it to listen on http and use SOAP for transport, and it has all the security and encryption functionality built in. This is a better solution if you potentially want to have your service called by non-.NET clients, or if you may want to reuse your service logic in other non-web applications. There's a little more learning curve, but a lot more power and flexibility.
You should be able to google for tutorials/walkthroughs for both asmx and WCF -- if it is an older tutorial and doesn't say "WCF", it's probably asmx. For WCF services, I have really liked the Service Factory from Microsoft patterns & practices, it gives a lot of good code generation and a designer surface to plan out your services and generates and configures projects to host them.