I don't think it is very important to find the location of Svcutil.exe. You can use Visual Studio Command prompt to execute directly without its absolute path,
Syntax:
svcutil.exe /language:[vb|cs] /out:[YourClassName].[cs|vb] /config:[YourAppConfigFile.config] [YourServiceAddress]
example:
svcutil.exe /language:cs /out:MyClientClass.cs /config:app.config http://localhost:8370/MyService/