Try a couple places that specialize in shower doors:

http://www.showerdoorcanada.com/
http://www.lineaaqua.net/about.php

Most glass companies (Binswanger, etc.) will build custom doors and are often cheaper than ready made doors. The most important issue with frameless-type doors is to make sure the threshold of your shower slopes toward the inside (rather than being level) or the door will drip water outside the shower (so I was told).

Good point. One of my local glass places does them, and probably does the installs, too.

Thanks homebound and native_tx for your input!

I did consider getting frameless custom doors (they're lovely), but the only option the builder gave without significant extra cost was for semi-frameless (ie. with top and bottom metal rails). And of course, now he states that he CAN'T FIND ANY DOORS that will fit my shower. The usual standard height is 71", too tall for my shower. It would be easier to tell him that there is such a door on the market, rather than ask him to provide a custom door.

I looked on the showerdoorcanada and the lineaaqua sites that homebound suggested and neither seem to carry frameless sliding shower doors less than 70" in height.

Any other suggestions?