What is the process for adding an external structure to a house

[Daniel Miller]

We want to have a permanent patio built onto our house (Fremont, CA).  Up until now, every year once the rainy season ends, we've been putting up a heavy-duty tarp; 12'x10', two corners attached to our eaves and two held up with 10' wood poles, attached with cords to posts pushed into the ground.  When the windy season (or rain, if we get any in a given year) arrives in autumn, I take it down; the tarp generally lasts 2-3 years before needing replacement.

Anyway, I'd like to replace that with a robust permanent structure, which I'm envisioning as being a similar structure as the tarp thing; two corners attached to 2x4s in the eaves, the other two out in the yard attached to a 2x4 or 4x4 set of wood posts, fastened securely to the cement surface in the yard.  The top should be well-supported wood panel design, possibly with the same composite-tile surface that our roof has...

So, I searched on Yelp for general contractors who had good user ratings; the first two wouldn't even discuss such a small job; the third asked me 'do you have drawings?' ... ummm... no, I don't... he said he would talk to his people and call me back, but he never did so... I'm taking that as a "no bid" situation...

So now I'm a little baffled... am I really going to have to hire an architectural engineering firm to generate drawings, for such a simple project?  This is almost sounding like a 10s-of-thousands-of-dollars job... that is *not* what I was envisioning...  I mean, if I *have* to, I can just stick with the tarp-and-poles solution that we've used for the past 20 years or so...

So I'm back here at BiggerPockets again, looking for insight and wisdom... are architectural drawings really necessary for a job like this?  

And the big question: how do I select contractors (or whatever else is needed) for a job of this scale??