To get started with the forward jet tree maker do:

klog
cvs co offline/FUP/
At the point of this writing you will get three directories in offline/StRoot/FUP (see here http://www.star.bnl.gov/cgi-bin/protected/cvsweb.cgi/offline/FUP/StRoot/)
-StFwdJetTreeMaker
---Reads in tppmc, smeared and unsmeared trees. This can be optimized since the tppmc tree and the unsmeared tree have the same info
---The maker constructs smeared and unsmeared jets and provides matching maps between the jets and partons and the smeared and unsmeared particles
----jets, particles and partons are available in vector<TLorentzVector> objects. Refer to the header file.
---- particles for each jet are in vectors of TParticle vectors . The outer vector is indexed like the corresponding jet, i.e. the first entry has the particles of the first jet.

----There are also map<int,int> objects that map detector to particle jets and detector/particle jets to the matched partons.
----other fields give x, Q2 values as well as parent proton spin

-StFwdPlotMaker
---This maker grabs the StFwdJetTreeMaker and produces plots like jet energy resolution etc...
---Have a look how to use the treeMaker

-StFwdCollinsMaker
---uses the treeMaker to get jets and particles to create collins asymmetries


Compile:
There is a script in StRoot called "compile" that compiles the three makers. There are some libraries that have to included and flags to be set. This is done by the script.
It should work under dev if the compile script is run in the parent directory (FUP in this case).

macro to run it all..
run
root4star -b -q StRoot/StFwdCollinsMaker/macros/run.C
This macro uses all three makers to compute collins asymmetries for particle/detector and parton jets.