Can anyone think of any prepositions/prefices other than these:
se
de
inter
circum
per
a/ab/abs
ad
super
ultra
infra
extra
intra
sub
contra
prae
pro
ante
iuxta
cum/con
prope
apud
in
e/ex
usque
propter
sine
ob/obs
post
re/red
supra?
Ingrid
Thanks.
I need more brains! 
cum / com / con / co
ob / obs / o / os
praeter
sub/sus/su
subter
trans/tra
amb/am/an
au
dis/di/dir
ne
neg
por
adversum / adversus / ad …versus
circa
citra/cis
erga
penes
praeter
prope/propius/proxime
secundum
supra
versus
coram
tenus
So, I think we have the most frequent ones. Although, some of these can only be used as prepositions, others only as prefixes and others as both. E. g.: au (aufugere) or amb/am/an (ambire, amplecti, anquirere) can only be used as a prefix. But you figuered that out for yourself. 
I hope I helped you. What do you need this for anyway?
Greetz
Philippus Moerus.