Back to the OP's issue of why he got ignored…
Simple - you were too much work. Too high maintenance.
Now, before you get mad let me explain. Unless you come to the GC with a buildable plan - i.e., finished drawings an plot map - there are too many variables to quantify. To name a few:
What kind of foundation do you want? This could include the thickness and finish of the concrete. And that's ASSUMING you want concrete…
Do you want 2x4 or 2x6 walls? Or something else?
What kind of roof do you want? Which way does the ridge go? What pitch? What kind of shingles? (p.s. - it's MORE hassle if you tell me to "match the house" if you don't know what mfr. and style those shingles are.)
What doors and windows are wanted? Is he providing the OH door?
I could go on for pages, but these are the kind of things that make it impossible to give you a bid, and make this situation a contractor's nightmare. I, too, would walk away…but at least I'd tell you why. Or if I needed work I might offer to help you come up with a plan - for a price.
So - you wanted to vent? Now you see the other side. Hopefully it helps you understand how to approach the NEXT contractor in a manner that allows him to HELP you...
MN4X4 raises a lot of good points here. I've had GCs do a lot of work for me in both Ohio and Virginia so can see this discussion from both points of view.
First of all, the GOOD GCs usually have plenty of work and are quite busy. They don't have time to spend it running around working up bids for dreamers. They are good precisely because they focus on their current job, so you have to be willing to stand in line and give them time to respond.
When they do respond (and the good ones nearly always get back to you, just maybe not as quick as you would like) be ready to show them a solid plan that proves you are serious about the project. When the GC shows up for the first visit with you, be ready to prove you are serious:
1) Have a set of decent drawings ready to talk over, not a bunch of chicken scratches on a notepad;
2) Have a specification that lists a lot of the details that MN4X4 is talking about;
3) Have the planned site staked out with the approximate building corners so the GC can get a quick picture of location, drainage, access, etc.;
4) Have the building permit in your hands and give the GC a copy. GCs usually hate to screw around getting permits from the local bureaucrats using someone elses weak drawings; and lastly,
5) Don't be a jerk and try to prove how much you know about construction. Politely talk over the plans, spec, etc. and listen to the GC's questions and comments. If you don't make a cooperative impression, or if he gets bad vibes about you, he won't be interested in your project.
Then be ready to wait until he has time to work up a bid and get back to you. These GCs don't usually have a staff of estimaters sitting in some office somewhere. The GC will usually have to work up the bid himself on a rainy afternoon or some Sunday afternoon between family events etc. This effort of the bid prep takes time so he needs to know you are serious about the job.
And if you expect to get a GOOD GC at discount prices, you're dreaming. He is good because his work is precise, he pays attention to detail, he keeps his work sites clean, he pays his good helpers a decent wage, and he stands behind his work and corrects his errors. None of this is cheap.
And a final thing that a good GC does is give you a response. Despite how busy he may be, it only takes a few minutes to give you a call back and let you know if he's interested or not. If a GC isn't interested in doing a project for me that's OK, I don't even need to hear a reason why, but at least give me a call back and tell me if not interested. Then I can move on to someone else. Leaving potential clients/customers hanging in limbo with no response is grossly unprofessional.