Contact your nearest chapter of The American Institute of Architects for a referral(s).

You can also check the find professionals here on Houzz. Generally, (not always), for a few bucks more you will get better design from architects than home designers. Also, let us know where you are. Chances are someone here may know a good architect in your area.

Check out home construction projects in the area you plan to build to see what architects they used. Talk to the builder and home owner to see what their experiences are with the architect.

I prefer using an architect (surprise); they have the education, experience, and testing that help guarantee the best results.

Generally an architect will provide much greater value than a designer or draftsperson. There are exceptions though. As said above, look around at houses in your area that you like and look at architects websites. Before finalizing anything get some references and talk to them, what did they like what didn't they like, what do they wish has handled differently, would they use this architect again, etc.

Then, rather than a sketch-up I'd give your architect or designer a list of requirements and desires in somewhat critical order including budget, rooms, approx space, features, styles, etc. You'll likely end up with a much better outcome this way than trying to modify something you've drawn up.