To automaticly apply sound changes, I propose the SCA, a sub-site of zompist.com. (sca2 - sound change applier)
Perhaps my favorite single example of name change by accretion is Torpenhow Hill, which literally means Hill Hill Hill Hill. Each successive simply added their own word to the thing.
I belive you may be looking for a portuguese/spanish-english dictionary. those languages were basicaly formed by a combination of greek and latin with a long time 'deterioration' and influence of the cultures they scame in touch around the world (mostly english and french, but brazilian portuguese have influences of native americans and the languages of the many countryies the slaves were brought from)
luckly I happen to have a list of greek and latin prefixs that are used in brazilian portuguese saved on my favs tab, so I'm posting it here to make your work faster... well, not that looking up on wikipedia would take too long though.
Anexo:Lista de prefixos e radicais gregos e latinos ? Wikipédia, a enciclopédia livre
you may need to translate the portuguese parts on google