I like TortoiseSVN's windows integration, Is there something like that for dealing with git-svn? I'd even go with a less integrated GUI if it is quick enough to access. What I don't want is a CLI as I rarely would have a command prompt sitting in the correct directly.
This is a related question but for Linux
The easiest way I found was to use the git gui, and add a git svn dcommit and git svn rebase command to the Tools menu.
If you install msysGit, it will even put a 'Git GUI here' command in your context menu.
This has the advantage of not requiring any additional software apart from git itself, and will work on every platform that git (gui) runs on.
Edit: I should mention that this is exactly the way I have been productively using git against our svn-repos for a few months now. Works just fine. And it's the same on Windows, Linux, whatever. So no need to use different tools for the same job, depending on the OS.
TortoiseGit (http://code.google.com/p/tortoisegit/) added basic support for git-svn in release 0.8.1.0:
The release log says:
Add Basic Git-SVN Operation:
Add SVN DCommit Command
Add "SVN Rebase" and "SVN DCommit" command at shell contextmenu
Support Git svn-clone at clone dialog.
A sideways and very late answer, but maybe useful to later spectators, re why you don't want a CLI; assuming you're using XP install the Microsoft Command Prompt Here Powertoy which gives you an Explorer right-click shortcut on a folder. I use it all the time. Windows 7 has the feature out of the box, but you have to hold down some key while you right click, I think.. shift or alt or something.
Also, Tortoisegit now apparently has git-svn features, I am going to check them out..