KidBlue -
Yes, you should be able to find such a place. You can do an MLS search on
www.moveolympia.com. Use the "Advanced Search" function and you can specify lot size above three acres. I did a quick search in the 400K-500K price range and found 29 properties, scattered throughout the outskirts of Tumwater and Olympia. Most were located in the "South County" area, meaning rural Tumwater, Rochester, Yelm, and the space in between. If you stick to the Tumwater listings, you'll only be about 15-20 minutes outside of both Tumwater and Olympia.
Tumwater is definitely on the upswing. The town was stagnant for years when I was growing up, but the need for housing finally put the South County areas into play. Now there are lots of new neighborhoods springing up. Still, there are larger lots available in the price range you're looking at.
I used to bike quite a bit in the areas you'll be looking at, so let me know if you have specific questions. I may or may not be able to help.