If you have no budget restraints, then get the D3300 instead of D3200. The D3300 with its kit lense makes an excellent combo for general shooting, and the kit at 55mm can do 1:0.3 (that is 1/3 of the original size).
For more magnification you need a macro lense, and as others have advised the longer the focal length the better, as you can then maintain your distance from the spider
You will also need a powerful external flash. As most of macro shots are between F/11 and F/32, you need a powerful flash.
To calculate the guide number
. Min Aperture : F/32
. Max distance : 3 feet
. Minimum ISO : 100
so guide number should be approximately 3x32 ~ 100 feet at ISO 100. If you use larger apertures or shoot closer the guide number required will decrease. It will also decrease with increase in ISO.
You can also consider the Nikon Macro Flash system R1C1
R1C1 Wireless Close-Up Speedlight System from Nikon
This comes with two flashes a mounting ring and the commander module which is required as the D3xxx and the D5xxx do not have flash commander mode. You can also get the above system without commander module, but then you will need at least a D7000 body.