This is a complex question.

First, I installed MT into a subdomain so I could learn it before I put it in my main directory.  My site is www.whatever.com

It is located at:

http://here.whatever.com

However in order to access it I have to use the URL:
http://here.whatever.com/db

Is there a way to access the blog without the /db?

Also, I am ready to move it to my main domain.  Do I have to re-install it into the main domain or can I link it from the subdomain?  I want the MT blog to be at:

http://whatever.com

Is this possible?

Some of your question might need to be answered by your ISP. I don't know what directory structure they require, or how they handle subdomains.

That said, your blog's Local Site Path (Under Blog Config) dictates the URL you must use. For example, if your Local Site Path might be something like:

In that case, the /home/justjaimelyn/www part probably maps to whatever.com, while the addition of /here makes it work as here.whatever.com. Assuming you don't have a bunch of other stuff in the 'here' directory, you could just take the /db off the end of your local site path and rebuild.

That gets a little bit more complicated if you have used hard-coded URls in your templates, but hopefully you haven't. Your archives can either move, too, or be left alone, it's up to you.

As far as moving the blog to your main domain, I would again only be concerned about what might already be there and whether or not you want to overwrite it. If you do, it's the same sort of thing. Given the example path listed above, you would change the Local Site Path to just /home/justjaimelyn/www

Please, be very careful before making any changes to your local site path, since your templates are quite possibly dependent on the location everything is in right now. You'll almost certainly have to manually move any images, by the way.

I hope that helps.

That helped a lot.  I am going to try and tackle it all today.  Thank you for your help.