Please help me - I have multiple domains that I want to use to promote my site

I have multiple domains to promote my site.  I take it that it is best to build them like Brochure sites that link to and refer to the target site and promote them with backlinks and just like a regular site to be valuable.  If you manage to get them ranking high and do a 301 re-direct, does that make that site disappearfrom google and what happens to its page rank?  What is the best idea for this.  An example might be a main site of "Cherrytrees.com" and a second supporting site "thebestcherrytree.com".

I will sure appreciate your input and ideas.

Tule

Tule ,
301 page and 404 page is more important for SEO .

Well its been a good strategy to promote the main site but you should not forget that the links you are going to build for your main site should be quality links not just to have them from poor page ranks or bad links.