Do you have a domain in mind? If you do, and it's available - buy it NOW. It may not be available afterwards and if you really want it they could sell it on to you at a much higher price.
Create the majority of the website and then order your products. Whilst you are waiting for your products to arrive, contact businesses or whoever you want to sell the product to and finish improving your website. On your website, have boxes saying the exact size of adverts and put like "Your Ad Here" in the box or something so that people know what space is available to buy.
Businesses aren't going to want to see an idea, they are gonna want to see the full thing ready and waiting.
Hope some of that information helps,
Luke
Follow my Twitter: @LR_Jordan
Read my blog: www.lukesroadtobusiness.blogspot.com
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