I am just over 5' and have a couple of suggestions. I fully recommend Bike Friday (have just got a petite crusoe). They are light & fantastic for the smaller rider. BUT - they are expensive, and I don't feel they are ideal for a newbie (they require a fair bit of fiddling - unless you never fold it - then you are paying a lot for an advantage you won't ever use).

An alternative suggestion is Giant. They do a 24" wheeled bike which I think is aimed at the youth market - but might be just right. They also do a road bike with 650c wheels in a very small size.

As I am the proud owner of at least 6 bikes I am very happy to help out w/ any advice - feel free to email me offline, or via the forum.

Corinne