Ambient techno isn't quite what you're looking for. You probably want some sort of melodic/ambient/psy trance. Ambient stuff is more along the lines of really mellow ambient noises (ala aphex twins - assorted ambient works), which most definetly will put you to sleep on a road trip.
I have several free-to-distribute DJ mixes that make awesome road-trip cds (trance, dnb, house). If you aren't too opposed to downloading 600 meg files to put on cds, I can help you out.
Here's a link to an awesome down-tempo/trip-hop mix.
http://twinfirs.com/mohaj/21Apr04.mp3
here's a faster DnB set you may enjoy
http://djsyze.com/MIX/SYZE3.4.04.mp3
A. Simpson (local dj) has some good stuff too
http://aaronsimpson.com/audio.html
&
http://aaronsimpson.com/older_mixes.html for his trance
if you need more suggestions, aim me krgswitch or email the_dj_glitch (at) hotmail (dot) com
</sarcasm>
<Anovis> mmmm I wanna lick your wet, Mentis.
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