Depends on what camera you are using. If you want good close up nib shots you really need a camera that can take a macro lens. Doesn't have to be a SLR as some mirror-less cameras now have changeable lenses.
My recomendations:
Cheep and cheerful (£130): Sigma 70-300mm f4-5.6 can be used for day to day photos as well, no image stabilisation, not so great for shallow DOF or in low light (f4 min aperture at 70mm)
Middle Ground (£380): Sigma 105mm f2.8 with a min focusing distance of 32cm this lens works well for close-ups of almost anything form small things like nibs, to cropped portraits. Produces lovely quality photos with good bokeh. Wide aperture so can do pretty shallow DOF and low light well. Note this is a prime lens and can not be zoomed.
"I have way to much money to spend on a macro lens unless this is my job" (£1100-1300): Sigma 180mm f2.8, this is about as good as it gets for close ups. Just don't expect it to take to many wide angle shots. All the + points of the 105mm at 180mm but with a slightly further min focus distance of 46mm.
You should also consider investing in a light box, even without a good camera it makes a big difference and you can buy one for about £40, or make one for less.
Most importantly, as with any photography keep experimenting, it can take a lot of time and patience to get the shot you want. Dont give up.
Afternote: I game sigma lenses as an example as they make variants for most of the major manufacturers. Own-camera brand lenses are also available, Tamron also make lenses for most brands. I chose sigma over tamron as I have more experience with sigma lenses, and can vouch better for their quality.