Need advice about Cob and materials.

I live in Tomball tx. I'm right outside of Houston in the country.
I have been obsessed with wanting to build a tiny home with Cob  for years.
And it's time for waiting.

I already know the main Recipe  for cob but don't want to have to buy anything at all.
My idea is to build with all natural resources found in nature and on my land. How can I mix Cob without having to go and order Straw or Sand?
If there are any other methods for making cob please educate me.

I would like to start work ASAP.

Hello Rodney,   Thank you for your post. To get right down to it, the straw part does not have to be just that, it could be any fibrous material strong enough to provide tensile strength that the other two materials don't have. Straw is mainly used as its usually locally available and inexpensive to purchase in the quantities needed even for a small house, but really it can be any long dried grass. As long as you can pull and twist it (when dried) without it breaking very easy, than its probably a good candidate. A little searching around in fields or abandoned sites might turn up some good stuff.
As for the sand, if you can't find any on your property or don't want to dig an ugly hole, maybe someone in the area is digging a foundation, doing road work or construction that would like to get rid of it.  Just make sure that for cob, the sand is not round in texture (like beach sand) but rather angular and more coarse so that there is good surface area to bind the particles together making for a stronger wall.
The Cob Builders Handbook by Becky Bee or The Hand Sculpted House by Ianto Evans/Cob Cottage Company are awesome books on the subject and worth looking into.