JPH,
I hope you have read my near field line array white paper but if not, you can download it at the link below. The white paper will cover many of the questions you raised--height of line/number of drivers, near field extent, etc. Understanding that paper will help you in your project planning/design.
The Linus 2 design (larger array in the picture) uses 10 Vifa TC14 and 8 Silver Flute YAG20-1 (or Parts Express Pt2) per side. The Linus 2 is a true top to bottom near field array. The entire room would be in the near field. The Linus 2 kit was available through Rick Craig's Selah Audio (www.selahaudio.com) but he has recently moved on to high end arrays. You can contact me for info on the Linus 2.
The Needles array--smaller ones in the photo--use a single high quality Aurum Cantus G3 ribbon tweeter in the middle of 16 Tang Band W3-371S drivers is what I call a quasi-line array--it is not a true near field array but has many of the same virtues. The single height and distance from the established within the room. The Needles array is available as a kit from Creative Sound Solutions (http://www.creativesound.ca/details.php?model=NEEDLES).
Jim