#2. "RE: Question about Nikon close-up attachment lenses" In response to Reply # 0
They normally sell on ebay for $100-$200 each. Other places they can be purchased for less. I haven't gotten one in a year or two but one well respected online vendor was selling used ones for $29.00 each. I picked up several from them.
#3. "RE: Question about Nikon close-up attachment lenses" In response to Reply # 0
The 5T and 6T tend to run around $100 each. Optically they are quite good - and stackable. Close up lenses do add glass whcih can be a disadvantage, but the quality of the Nikon 5T and 6T is excellent.
The 5T and 6T work very well with the Nikon 105 macro lens. They also work well with the 70-300 and an adapter ring.