Yes, this is the wrong place.
I think it would be better if you´d post your questions in the
“Questions+Troubleshoting Forum” .
http://www.zbrushcentral.com/zbc/forumdisplay.php?f=8
There´s also a brand new Support-Center( registration is very simple)
http://support.pixologic.com/
Regarding your question-it is possible. 
I never did that because I never had a seperate head,
but I hope the following links will help you.
You can append the body to your head as a SubTool if you have already modelled a body:
http://www.pixologic.com/docs/index.php/Appending_Subtools
Also you can build the body easily with Zspheres.Simply append a Zsphere (Tool:Subtool:Append-Zsphere).
With this method you can be sure the body will fit perfect to the head:
http://www.pixologic.com/docs/index.php/ZSpheres_and_SubTools
You can combine both SubTools (only if you want to) with different methods.
Combining SubTools with “Insert mesh”:
http://www.pixologic.com/docs/index.php/Tips_For_Working_With_Subtools
Topology ( I´m not sure if this is the correct link for combining. If somebody knows another please let me know…or better-let nico know
and post it here)
http://www.pixologic.com/docs/index.php/Topology:_Mesh_Editing
Merge the SubTools together (Note:you´ll need the “SubTool Master Plugin” it´s also useful for a lot of other things.).
You can download it here:
[color=cyan]http://www.zbrushcentral.com/zbc/showthread.php?t=057154
Also check out the “Did you know that” thread.
There you´ll find very usful tips+tricks.
For example “How to merge SubTools and be able to sculpt across the tool without having the seam spread apart”
http://www.zbrushcentral.com/zbc/showthread.php?t=61676&page=1&pp=15
Hope that´ll help you out. 
Happy Zbrushing!