Create custom service in Windows 7

The link you have provided also points towards Trac On Windows [link is now bad], which seems a pretty complete description of the installation process.

In section 3 I find the following line:

sc create svnserver binpath="C:\Subversion\bin\svnserve.exe --service -r c:\svnrepositories" displayname= "Subversion Server (svnserver)" depend= Tcpip start= auto

which creates a system service. However, I don't know if that's the service you need.

yep srvany seems to be only way - unless someone else knows another way using

"sc create /?" in cmd prompt (i dont)

If you're scared by the command line and not scared to spend money, then FireDaemon allows you to easily set up services.