Are you going to be in Lot 1? I think the realtor's elevation map is probably the best to go off of for now, though it may be useful to see if other sources match up. The ideal would be to actually
map the contours yourself. A nice way to balance it would be to first make a plan with the info you find online and with the realtor, then when you are actually on the land, you can fine tune and correct the plan.
Here are some resources you can check out:
Weather:
Weather Underground is useful for just about everything weather related. Lots of data.
RSS Weather is good for getting nice climate graphs to look at.
If you enjoy visuals,
Weather Spark has the temperature, wind directions, daylight/nighttime hours, and more information organized in pretty graphs. When you do a search, be sure to check the "Averages" selection to get the graphs. You can get the graphs from dashboard view, just have to get used to their interface.
Soil:
The
WEb Soil Survey contains a lot of information about soil types in the USA.
Contour/Elevation:
National Map Viewer is a good resource for people in the USA to check the contours of their land.
Sun:
The
Sun Position Calculator is a good place to start to see where the sun will come from and how it will travel across the sky. It also provides solar declination information, too.
Sun Calc is another nice website that does the same thing. The
Solar Electricity Handbook has good info for designing the angle of solar panels. If you want to visit the site to get the info, a
clinometer may be useful.
Plants:
The
Plants For a Future Database is a great resource to find what could possibly grow in your area.
People:
It might be useful to check a local library, county office, or city office to check some of the records on the land. Seeing what nearby
transition network folks and
permaculture people are doing may also be helpful.
Other Useful Stuff:
To get yourself in the mindset and see what information you will need, filling out
one or
two permaculture design client questionnaires might also be useful.
The
Open Permaculture School has a full online lecture series about permaculture design, and if you want to, at the end of it, you can get certified. The certification costs money, but not the course.
Paul Wheaton's keynote on permaculture provides a nice overview of 72 bricks of permaculture.
Geoff Lawton and
Permaculture News are also great resources. There is also a cool
lecture series by Bill Mollison online.