I've been talking with a girl for most of a week, and it's going just about as well as it could be in my view, so I just want to know when is the right time to suggest we meet. Too early and she'll think I'm overly keen or just after sex or something, too late and she'll have moved on/got bored/found someone else.
Sooner rather than later. I usually wait until she seems comfortable with me which shouldn't take more than a few days. Either she's interested in actually meeting you or she's not, and i doubt trying to text with her for weeks is going to change that too much