Check under the back seat up inside the springs, this is where a friend and myself finally found his snake after three days of searching. As much work as it's going to be if you don't find him there, unbolt the front seats as well. What kind of car is it? I know that doesn't seem it should matter, but the Chilton's manuals can tell you exactly where the panels are that cover the screws which hold in the dash, so check for a manual for your car online, of course you'll have to purchase the dang thing, but they're handy to have anyway.
That snake of Dean's was coiled up in the springs underneath the lower portion of the back seat for three days in the fall, not a happy camper!
http://www.morningstar.sophiagroup.org/cgi-morningstar/ikonboard.cgi - Serpents of the Morning Star
http://www.sophiagroup.org/cgi-sophiagroup/ikonboard.cgi - Sophiagroup
"He who always gets the last word, is generally the least intelligent speaker!"