How to exclude files and directories in modrewrite

I have a website at:
www.MySuperGasPill.com

Right now if you goto www.MySuperGasPill.com/testing

I have an APACHE rewrite that takes anything after the / and puts index.php?host_id="whatever is after the /"

This works but the problem is, I can't go anywhere else on the site because it's always rewriting the URL to that variable.
SO what I need to know is, is there a way in my .htaccess file to make it so that this doesn't happen. If so how? Here's my htaccess file as it stands right now:

RewriteEngine on
RewriteCond %{REQUEST_URI} !^/index\.php
RewriteCond %{REQUEST_URI} !\.jpg$
RewriteCond %{REQUEST_URI} !\.png$
RewriteCond %{REQUEST_URI} !\.gif$
RewriteCond %{REQUEST_URI} !\.swf$
RewriteCond %{REQUEST_URI} !\.pdf$
RewriteCond %{REQUEST_URI} !\.doc$
RewriteCond %{REQUEST_URI} !\.css$
RewriteCond %{REQUEST_URI} !\monitor$
RewriteCond %{REQUEST_URI} !\css$
RewriteCond %{REQUEST_URI} !\thankyou$
RewriteRule ^([^/]+)/? index.php?host_id=$1 [L]

In my index.php file I have a function that looks at my database using the host_id in the url so that it knows which "Host Information" to put on the webite. Example: Host Name and Phone Number. Together with this, it also looks at the database to see which host to EMAIL the lead to. This is VITAL.

Now, the problem is if I try to use ANYTHING on that domain such as www.mysupergaspill.com/thankyou...then it's obviously thinking "thankyou" is the host_id. I don't want that. Plus I need to be able to create an admin area for my users to manage their leads...I obviously can't do that the way it is now because if my customers goto www.mysupergaspill.com/admin then I run into the same problem.

SO I think I've made myself clear here as to what my problem is and the solution I'm looking for. I'd be very grateful for some help. And while you're at it, if you wanna check out the biz opportunity too...you'd be wise to do so.

Thanks!