60mm micro (nikon)
105mm micro (nikon)
150 or 180mm sigma
Tamron 90mm (?)
Just look for 1:1 ratio (f numbers usually around 2.8 or 3.5)
Depends how close you want to get to the subject. Think someone posted a link to a site that basically was:
60mm - harmless
105mm - skittish
150mm - possibly dangerous/moves at slightest movement
180mm - positively dangerous... ie poisonous snakes - more distance between you and it...
I have the 180mm on my wish list... dunno if I would ever use it tho
+1
All depends on what you photograph.
The shorter focal lengths are easier to handhold, but the longer focal lengths can get you the shot from further away with more diffuse background blur.
The 150mm is a nice compromise, it's noticeably longer than the short lenses but not as big and heavy as 180/200mm. It's also got great build quality with a HSM motor (which isn't that fast, but mine's always reliable and easily good enough for general purpose), and a lot quieter than the AF in the 70 or sigma 105mm's.
If most of your stuff is done on a tripod, then the sigma 180mm is a real bargain used. It's very similar to the 150mm in build/IQ, but you get that extra length (with the sacrifice of weight and 2/3 of a stop). It was recently discontinued, but that is only because the 150mm was more popular. The 180's go pretty cheap
second hand now, and I wouldn't be surprised if their used price starts to increase as they become harder to find.
The tamron 60mm f/2 gets good reviews for a lightweight shorter lens, plus it's the widest macro lens you can get if you want it to double as a general purpose/portrait lens. But some reviewers have reported aperture problems, so might be worth reading more into.
The sigma 70mm f/2.8 is rarely mentioned, but it's uber sharp wide open, even more so than the 105/150mm offerings (thought they're all the same once you stop them down 1-2 stops which you always will for macro).
Don't know much about the nikkor 105VR, but I only ever hear good things about it from it's users.
I believe there are also older versions of the nikkor 105 that lack VR but will have the same great build quality if you don't need VR.