help required in url rewriting

hi there...
i am new to url rewriting and this forum as well
can any one help me rewriting url???
here is my problem!!!!!!!!!!!!!!!!!!!!!!!!

@ root dir i have pages like:
index.php, search.php, etc

Folder of css
Folder of images
Folder of uploads

Problem:::
css files on index and all the pages are coming form css folder
some of the images are coming form images folder and rest are coming
from uploads.

what i have to do is :::::
i have to rewrite urls
http://domain.com/posters/index.php?pag=news
http://domain.com/posters/index.php?pag=news1
http://domain.com/posters/index.php?pag=about
to
http://domain.com/posters/pag/news
http://domain.com/posters/pag/news1
http://domain.com/posters/pag/about

here is my solutions::::

RewriteEngine on
RewriteRule ^catid/([0-9]+)$ /posters/index.php?catid=$1 [R]
ReWriteRule ^pag/([a-z]+)$ /posters/index.php?pag=$1 [R]
ReWriteRule ^pag/css/([a-z]+.[a-z]+)$ /posters/css/$1 [R]
ReWriteRule ^pag/images/([a-z]+_[0-9]+.jpg)$ /posters/images/$1 [R]
ReWriteRule ^/catid/uploads/([a-z]+.jpg)$ /posters/uploads/$1 [R]
ReWriteRule ^catid/css/([a-z]+.[a-z]+)$ /posters/css/$1 [R]
ReWriteRule ^catid/images/([a-z]+_[0-9]+.jpg)$ /posters/images/$1 [R]
ReWriteRule ^/catid/uploads/([a-z]+.jpg)$ /posters/uploads/$1 [R]
RewriteRule ^subcat/([0-9]+)$ /posters/index.php?catid=$1 [R]
ReWriteRule ^subcat/css/([a-z]+.[a-z]+)$ /posters/css/$1 [R]
ReWriteRule ^subcat/images/([a-z]+_[0-9]+.jpg)$ /posters/images/$1 [R]
ReWriteRule ^/subcat/uploads/([a-z]+.jpg)$ /posters/uploads/$1 [R]

######################################################################
problem with this solutions!!!!!!!!!!

when i place this url in browser ........
http://www.artologics.com/posters/pag/aboutus
browser sends me to right place but it replaces url with
http://www.artologics.com/posters/index.php?pag=aboutus
plz. help me if you can???????
---------------------------------
Muhammad Abdul Mannan
itsmani1@hotmail.com
itsmani@gmail.com
http://mannan.zabvision.edu.pk
http://itsmani1.sphosting.com

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