If you are willing to build an ultralight with traditional building techniques then you might want to check out the Legal Eagle XL. It is designed for 575lb gross so that leaves well over 300lbs for fuel and pilot. Here is my Legal Eagle XL site:
http://eaglexl-58.com
A real attraction of the Eagle is the four-stroke 1/2VW engine. I have ~250hrs Rotax two-stroke time but my interest has waned in flying anything other than a four-stroke.
Here are some videos from my Eagle:
http://www.youtube.com/user/EagleXL58?feature=mhee
Enjoy tire kicking!