Here's a summary of the line array speakers I'm aware of that are available from US manufacurers and distributors. I'm not going to embellish this post with any subjective remarks about price or sound quality, but there is a great range of both in the list below. I'm sure I'll miss some, especially any that are sold by distrubutors outside of North America, so please everybody fill in the blanks with those I've missed.
McIntosh Labs offers several models that are pictured on their web site
http://www.mcintoshlabs.com/IDS introduced a pair of full range driver arrays at the 2006 RMAF. Here's their web site
http://www.ids25.com/Epiphany offers several models
http://www.epiphanyaudio.com/Nearfield Acoustics offers the Pipedreams arrays
http://www.nearfieldacoustics.com/AV123 has taken advance orders and is on the verge of introducing two line array models designed by Danny Ritchie
http://www.av123.com/products_category_brand.php?section=speakers&brand=61GR Research offers two models, the LS-6 and the LS-9. They aren't listed on the GR Research web page just yet, but discussion about them can be found on the GR Research Circle
http://www.audiocircle.com/index.php?topic=43853.0Selah Audio offers two models, the Alexandrite and the XT-8, as completed speakers, plus one that's available as a kit, the RS-8. Rick Craig also offers custom designed speakers, some examples of which can be seen on the Selah Audio web page
http://www.selahaudio.com Zalytron offers several kits
http://www.zalytron.com/ Bill Fitzmaurice offers the plans for a line array that can be built very inexpensively
http://billfitzmaurice.com/TLAH.htmlDIY builders often build one-off line arrays using drivers that become available for attractive prices as "buyouts" from Parts Express and Madisound. The advantage of these is that they can be built cheaply and, if properly designed, can sound very good. The disadvantage is the can't be duplicated after the buyout drivers are sold out. Here's one example
http://www.lonesaguaro.com/speakers/array/array.htmReaders of this post, please respond with information on any line arrays I've missed.