I have a recurring scenario happening to me even though I'm sure the particular girl is interested in me.
I tell a girl I'm going to .... at such a time and ask if she wants to join me (it's always an activity that most would consider fun).

I get an answer like "well ummmm I'm not sure, you'll have to call me, here I'll give you my number (gives me her number) and proceeds to say why today may not work (usually something lame). So I bust on her about wanting to do that ... instead of what I'm suggesting.

I leave with the impression that the whole number thing was just another brush-off, and if I call her she's just going tell what she should have to my face "no thanks!".

What does a DJ do here, Not call, call and break the plans first, make her commit to yes or no right to my face.

Any Ideas ??

My suggestion is that you read the DJ bible. It has many suggestion on how to deal with these sort of situations.

Piss on it !
I've decided, I'm not calling her, and if she ever asks why I didn't I'll just pull a flaky-chic move "ummmm I'm not sure something came up" and the next time a chic gives me a lame ass answer I'll just keep rephrasing the question until I get a "YES ... such a time sounds good", or "NO THANKS" to my face.

Why can't you just ask her straight up, does she want to do it for real, or is she just stringing you along? Then tell her that if she's just going to reject you over the phone, you'll save her the trouble and give her back her number, and eject.