Here's the list from Smyth's Greek Grammar §839:
a. The primary suffixes ta:, te:r, tor, tro, eu, denoting the agent or doer of an action, are masculine.
b. The primary suffixes trid, tria:, teira:, tid, are feminine.
c. The same root or verb-stem may have different suffixes denoting the agent: gen-e-te:s, gen-e-te:r, gen-e-to:r, 'begetter'; math-e:-tris or math-e:-tria, 'female pupil', fem. of math-e:-tis.
d. Words in -te:r, -tris, -eus are oxytone. Words in -to:r, -teira, -tria have recessive accent. Words in -te:s are oxytone or paroxytone.
e. See also on (nom. -o:n) §861.18.
861.18: on (nom. -o:n: primary, in words of agency: tekt-o:n 'carpenter', trug-o:n 'turtle-dove' (truzo: 'murmur'), klud-o:n 'wave' (kluzo: 'dash'; and in others, as eik-o:n 'image' (oika 'am like'), khi-o:n 'snow'.
You can search Liddell & Scott online, by these endings to find actual words or give you a feel as to how words might be coined. Hope this helps.
