If you're serious about the project hire a designer to create the designs for you as layered PSD.
It sounds like you should be able to implement them yourself. I work with designers that are local to me, but you can find some pretty good ones on odesk.
you can get some inspiration from websites like themeforest(where you can buy some nice templates for cheap prices) once you have a theme you like you can implement that one or just adapt it to your needs but having a base to work on I think it's important. I understand you, I am a web developer, I can write css/javascript and anything I need but my taste is terrible. So that is what I usually do, I begin with a base and start to work on it, adapting, changing, adding and then I polish the result. It's not the best thing to do but usually works fine. If I had tons of money to spend I would probably do something different but since I don't...