That was the sound of you going down the rabbit hole, Tony. Welcome to the matrix :)
As far as lenses go, you've got two general options:
a) Sony E mount lenses with autofocus and electronic aperture
b) "Alt" (third party) manual focus, manual aperture lenses adapted to fit the NEX
c) Ok, technically there is a third option for Sony A mount (SLR) lenses... but big and heavy
The Sony E lenses are ok in my book, from what I've seen most of them are very decent. I've only used the 18-55. My main gripe is the limited line up, which doesn't make the most sense for a 1.5x crop body. This is the way I view the E-Mount lineup...
- 16/2.8 (24mm equivalent) - The somewhat fast aperture suggests that it might make for a 'normal' lens, but it's really too wide for that. Getting too close to people will distort their proportions. For landscape use the 18-55 @18mm is equally a good option at a similar focal length.
- 18-55 (27-83mm eq) - A very nicely built 'kit' lens. The image quality doesn't reach out and grab me but it's surprisingly good.
- 24/1.8 (36mm eq) - Not released yet. If this lens flops I think a lot of people will be disappointed, including me. If it's a good lens (which it should be at $1000) then it will really strengthen the overall lineup.
- 30/3.5 (45mm eq) - Short macro lenses are ok for flowers, you'll never get close enough to bugs to get the macro magnification. Slow-ish aperture for use as a normal lens.
- 50/1.8 (75mm eq) - Not released yet. The focal length is neither here nor there. Not wide enough for use as a 'normal' lens, a little short for a dedicated portrait lens. They should have made this either a 35/1.4 or 75/1.8, or 90/1.8
- 18-200 and 55-210 zooms - Well, these big zooms may be more useful for general travel. I don't think many UL backpackers will want/need them.
What Sony has done is created a really fine and interesting little camera in the NEX, but fallen short in their lens offerings. Even despite that the camera has been a HUGE hit in Japan (and around the world). The combination of a compact body, large sensor, and excellent sensor performance is a winner! Putting alt glass on digital cameras is nothing new, but the sensor on the NEX really shines with good lenses, and the small size makes for a very compact package when using the classic rangefinder lenses.
The classic manual focus lenses require a few things...
- First, an adapter to convert (whatever) mount to an E mount
- User must know how to manually focus
- User must know how to set the aperture on the lens
These are not difficult skills to acquire. Since the advent of cameras, photographers have been able to master these things. Prices range from dirt cheap to drain your bank account. Once you know what you're looking for eBay is a good place to shop. KEH is another.
edited to add a couple of "by the ways"...
1. A little self promotion, Tony you may want to read this on lenses if you have not already.
2. Congrats on having your photos selected for the Nat Geo book!