Texas Yankee:
I am a contractor in San Antonio, and I know how much we all love our decks down here in Texas. Concrete is for patios and for porches. Not for sitting 2-5 feet off the ground with a cold one to watch the sun set on the hill country. I personally like the organic quality of sitting on a wood deck an the feel of it under my feet.
A couple of thoughts: When I put down a deck frame work, cut away any vegetation, then go 4" below the frost line/vegetation roots with a
2'X2' hole. Depending on where you are, this is usually not too deep. I line the hole with sand to level the bottom out and put a 2'x2' concrete pad down. Then I use the deck blocks. I use 4' centers all around for this, and never have complaints.
Plan on an easy to apply wood finish every 2-3 years. When I build one out of any material, I tell the folks to get a cheap pump sprayer and a
5 gallon bucket (depending on deck size) and spray down the clean deck
30 days after we are finished. Spray again in six months. Spray again a year. Then as needed. I have seen well maintained decks stay around for 25 years and still look great, and zero maintanence decks go to crap in 2-3 years.
But the best advice I could think of for you is to go to the library and take a look at any of the 10,000 books on deck building. They are everywhere. They are at Half Price books. They are at Lowes. They are at Home Depot. In fact, I don't know if they still do it, but they used to do the design work as well as the material take off at Home Depot for free.
There are also some great programs around out there that you can buy that help you design your deck for appearance as well as structure.
You will hate yourself if you are pennywise and pound foolish on this. I know... I make a killing fixing homeowner built decks/gazebos/storage facilities/shops and all other manner of home made monstrosities where the "builder" doesn't plan or execute well. Slamming a pile of lumber together like they do on the home shows just won't cut it.
With so much information at your fingetips you should take another couple of weeks and work out all the logistics before you buy a board.
Robert
BTW... where in Texas are you?