I second the suggestion to check out trikes. A delta-style trike would sit higher off of the ground.

On the lower end is the old-style Sun EZ-3 Heavy and with lower end components, but they've been around for a long time. Lots of them in the used marketplace.
http://www.bicycleman.com/recumbents...ent-trikes.htm

There there are the new line of Sun trikes:
http://basicallybicycles.com/itemdetails.cfm?id=1077

The more expensive, upscale Greenspeed Anura:
http://www.gstrikes.com/anura_main.html

And the even more expensive Hase KettWiesel
http://www.bicycleman.com/recumbents...ent-trikes.htm