website naming

I think if the domain is taked by some other company then you dont have any option. you will have to go for the alternate. if you want the same name then you have to change the domain(either .net, org or any other). but if you want a specific ext like .com. then you will have to change the name, as you can take some short name or can add any string.
you are correct about the customer as they can get confused. but i think you can use or take the service of SEO so that most of the good search engine can show the correct website to your potential customer. as most of the users use search engines to look for a website.

goodluck

Hi! You can register another domain closely related to the first domain that has been taken. You can formulate one by basing on the contents/subject you want to put on that "would be" website.

As what the previous respondent said, SEO will be a good help to catch traffic to your domain. And absolutely put some investment on branding your domain through advertisement.

Truly speaking I dont have money to look up for such names so I never tried it. I like co.cc account rather than .com. Also it is unique and free. If you want to stay with .com then I would suggest you to insert some special letters in address like you already said. Better search over some blogs you will definitely got to read something as many people had already faced such things. Have you tried zoneedit website, it had displayed me thousands of custom domains yeasterday? It has potential to solve your problem, if you are going to pay them. Thanks and God bless