You may wish to consider an electric aircraft for your first aircraft, such as the multiplex easystar. However assuming you have experience with r/c aircraft, you could look at the Mugin 3m platform over at fpvflying.com.
Hope that helps
I'm working on a gas powered design using the new small (~35cc) 4-stroke engines you can get from Honda like the GX35 or the Chinese clones.
I haven't really found a good RTF or kit plane with decent landing gear. They always seem to be crappy little deals that break with almost any landing that isn't perfect. In most cases you're probably better off belly landing without landing gear.
What I have found though is that baby stroller wheels are about the right size and are very light. You can find them in dumpsters or at thrift stores like goodwill for dirt cheap. I really think you're best off making your own landing gear.
Maybe someone out there knows of a better setup, but if you want to take off from grass I think you usually need to make your own oversize landing gear.