You need a P. Eng. or an architect for the design. (And please don't say that with 9,000 sf you're on a "budget" and can't afford it.)

Subcontractors do NOT "design" homes. They follow the architect and engineer's plans that the codes office approves. You are getting way ahead of yourself if you don't have a set of building plans.

Actually Worthy, Texas doesn't require a P.Eng or architect to stamp residential plans. Some cities/counties do require one or the other but, as far as I know, Dallas does not. I would agree with you however that, for a 9000 sq ft residence, a homeowner NEEDS the guidance of a professional engineer and/or an architect. It would be different if OP planning to build a run-of-the-mill 1800 sq ft one-story rectangular ranch. But 9000 sq ft???? No Way!

Worse tho, it sounds as if OP thinks that one can have subcontractors design and build a house in "stages" rather than starting out with a complete unified set of plans before you ever consider breaking ground. (Eg, OP says he is looking for a foundation subcontractor to DESIGN and build the foundation and THEN he wants a framing subcontractor to DESIGN and build the frame.) Obviously, a foundation needs to be designed for the house that is going to sit on it so there is no way a foundation sub could design and build a foundation before knowing what the house plan (including the framing design) was going to be. DUH!

I do know that Dallas requires building permits and that one must submit building plans to them for approval before one can get a permit. So, unless OP is so clueless that he doesn't even know he needs a building permit, I have to assume he already has plans (designs) and just misspoke when he mentioned having the subcontractors DESIGN the foundation and framing. OP's plans may already have been drawn up by a licensed architect - although the way his posting reads, one can't really tell.

OP, if you serious about GCing your own residence, you might want to consider contracting with Owner-Builder Network - Dallas or a similar consulting company for guidance. Among other things, they'll provide lists of subcontractors that previous owner-builders have successfully used. And subcontractors that you find via an OBN referral are more likely to treat you like they would a larger contractor b/c your opinion of them and their work will affect whether they get additional work through the OBN.

OBN will also guide you through all the steps you need to take in building your home - including getting permits and scheduling required inspections. They can even help you get financing which can be difficult for an owner-builder.

I'm not pushing OBN specifically - although I do know several folks here in the Austin area that praise the Austin OBN office very highly. I've also heard good things about a couple of other consulting companies that have offices in the Dallas area including HelpUBuild and
UBuildIt so you might want to check out all three. There may also be some other that I don't know about.

Hope this helps.

Oh, and one more little bit of advice that is totally unrelated to building a home ... unless you want to wind up buried in spam email, do not EVER post your email on a forum like this. Spambots (electronic programs) troll heavily trafficked websites like Gardenweb looking for email addresses which the spambot recognizes by the "at" followed by "dot" symbols...doesn't even require that a human being ever read your post. To protect your email from spam, when you join GW you have the option of setting up your MYPage to allow GW to forward emails from other registered Gardenweb members to you. Then, just ask people to click on the MyPage link beside your name in order to email you. That way your email address isn't out there for a spambot to find.