How to be a foot model, petite model...?

For years, I’ve had people tell me I have beautiful feet. I could have cared less, but lately I’ve been strapped for cash and my mother in law sent a list of modeling agencies telling me I should go see them about being a model. She has a friend who used to do it, and I was wondering if any of you out there have any experience and/or suggestions to share with me.
Chiefly, how should I approach these agencies?
Do I need to prepare portfolios to leave with the agencies?
Also, since I’m 5’4" and 105 lbs, not freakishly beautiful, not nauseatingly cute, just the type of girl you might smile at as she jogs past with her dog, (I mean, kind of attractive in a sporty way) I’ve been told I should look into petite modeling, whatever the heck that really is, so any info anyone has to offer on that would be much appreciated.

So you wanna be a model

You probably don’t have to prepare a portfolio; most agencies will take shots of you for their own files. I’m not sure where you would find “part” modelling agencies, though.

Thanks Sublight!

Anybody out there with “parts model” or “real-life model” experience? The site Soyouwanna… seems geared more toward runway/fashion model stuff, so any info on the other aspects of modeling would be much appreciated.