Please forgive my being blunt (I'll blame the late hour) but you MUST learn about URLs and http://www.ietf.org/rfc/rfc2396.txt would be a GREAT place to start. Unfortunately, for you not to realize that
1. The domain name must be followed by a /
http://mysite.com?param1=value1¶m2=value2 is invalid while http://mysite.com/?param1=value1¶m2=value2 is valid - but ONLY because webservers can be told what the DirectoryIndex scripts are so that they will go fetch one, like index.php, and feed it the query string "param1=value1¶m2=value2". In other words, this URL is really http://mysite.com/index.php?param1=value1¶m2=value2AND
2. The ? marks the END of the URI string and the beginning of the query string
"param1=value1¶m2=value2" is the query string above as specified by the ? immediately preceeding it (the ? is just a marker (RESERVED CHARACTER) and has no other meaning - it simply canNOT be matched using any Apache variable).makes it extremely difficult for anyone to teach you much in the way of mod_rewrite - except to say that mod_rewrite CAN help you but only after you learn some Internet basics.
Since you've not shown your attempts at mod_rewrite code, I'll bet that you're writing RewriteRule statements to match the content of the query string. Know that ONLY RewriteCond statements can do that.
The linked article above is rather "geeky" in its specifications for the content of URL, URI and URNs but understanding the URI is critical to those dealing with websites and moreso to those writing mod_rewrite code.