At this stage good Graphic Designers, Copy Writers and Marketing Managers are critical to the success of the project.
In this scenario, agencies are ideal.
I have a background but am by not means a professional in the field.
In some projects I do end up helping with the initial kickoff concepts before engaging professional creative people, or just build a mockup. This page is a reference to the the resources I use to help get us there.
Inspiration starting point for picking out good logos - http://www.brandsoftheworld.com/
http://www.templates.com/ - collection of free and paid templates.
http://www.iconfinder.com/ - search engine linking to many free icons.
This has its own section.