Simple URL Rewrite Problems - apache

Question

I'm having trouble re-writing a simple URL with .htaccess.
The URL I am trying to rewrite is:
http://www.domain.com/index.php?page=PAGE_NAME
I would like the PAGE_NAME to be directly after the domain, for example if PAGE_NAME is blog:
http://www.domain.com/blog
At the moment I have tried the following with no success:
RewriteRule ^/?([a-zA-Z0-9_-]+)?$ index.php?page=$1
All help is really appreciated.
Thanks in advance.
My current .htaccess file:
<IfModule mod_rewrite.c>
Options +FollowSymLinks
Options +Indexes
RewriteEngine On
ErrorDocument 404 /search.php?page=notfound
# Add WWW to URL
RewriteCond %{HTTP_HOST} ^cristianrgreco\.com$ [NC]
RewriteRule ^(.*)$ http://www.cristianrgreco.com/$1 [L,R=301]
# Remove trailing slashes from end of URL
RewriteCond %{HTTP_HOST} !^\.cristianrgreco\.com$ [NC]
RewriteRule ^(.+)/$ http://%{HTTP_HOST}/$1 [L,R=301]
# Rewrite main page URLs
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /index\.php\?page=([^\ ]+) [NC]
RewriteRule ^ %1? [L,R=301]
RewriteRule ^([a-zA-Z0-9_-]+)$ index.php?page=$1 [L,NC]
# Rewrite download URLs
RewriteRule ^download/([a-zA-Z0-9._-]+)/?$ download.php?file=$1
# Rewrite page navigation links
RewriteRule ^(.+?)/page-([a-zA-Z0-9_-]+)?$ $1.php?currentpage=$2
# Rewrite article URLs
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^/?([a-zA-Z0-9_-]+)/([a-zA-Z0-9_-]+)/?$ articles.php?article=$2
# Remove file extension from PHP files
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{SCRIPT_FILENAME} !-d
RewriteRule ^([^\.]+)$ $1.php [NC,L,QSA]
</IfModule>

Answer 1

Try adding the following to the .htaccess file in the root directory of your site.
RewriteEngine on
RewriteBase /
#add these next 2 lines if you need to redirect http://www.domain.com/index.php?page=PAGE_NAME to http://www.domain.com/PAGE_NAME
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /index\.php\?page=([^\ ]+) [NC]
RewriteRule ^ %1? [L,R=301]
#send request to index.php
RewriteRule ^([a-zA-Z0-9_-]+)$ index.php?page=$1 [L,NC]