Some of my fellow ASP.NET developers use TortoiseSVN for their version control needs. They are a .NET development firm.
I've liked Subversion for version control, but might give TortoiseSVN or Git a try too.
While I have tried 3rd party controls, with the power of AJAX and such, I haven't had to use any of them for any client projects yet. One control we found very useful was I-Load. Especially handy for clients that want to upload and crop images when I had to build a custom admin backend for the client.