Where to look for inspiration when designing product/company website?

To begin with, let me say that "hire a designer" is not really an answer. Problem is, I will still have to evaluate and accept or reject whatever he or she creates. Personally I would go with a totally minimalistic design, but I bet many would consider it amateurish. I don't want to risk losing customers just because my personal taste is not very mainstream.

Where to get an idea what "modern", "professional" and "trustable" mean these days?

Spend a couple hours reading Smashing Magazine - They consistently post on many things regarding web design and development.

take a look at themeforest.net for an idea. We got our templates and images from them and their sister sites.

http://designshack.net/ has good collection too.

Will also look at themes offered for sale on volusion, shopify, 3dcart etc.

http://www.apple.com That is modern, professional and trustable.