im not sure if i put this in the right forums anyways im wonderin when it comes to search engine spiders are they able tell the difference

It makes no difference.

Can you be more specific? Difference of what? Virtual hosting and shared hosting maybe?

when the spiders goto the domain does it direct to the right place or is there a problem

Can you be more specific? Difference of what? Virtual hosting and shared hosting maybe?

AFAIK, the OP is asking if search engines care if multiple domains are on the same IP.

what im asking is does search engine spiders send the HTTP Host header

I suppose that each web site or web page unique for them by domain name not by IP address

yes they care about domain name not ip. Even if you drop your account you can see search engines display your site results for some more days

Due to ip justification/regulations, the majority of sites are name based (shared ip).

The search engines can easily see this, but it should not really cause any problem.

If you are trying to do PR link building yourself for SEO purposes, then different ips are only needed to disassociate themself. But other than that, it should not be any problem.

what im asking is does search engine spiders send the HTTP Host header

Yes they do. Vast majority of sites are served via shared ips. If SE bots did not specify the host name they want they would not be able to spider the web.