Is there an easy way importing data to Oracle database

hiyee, im a newbie here in this field and i need help..i am doing a database centralization project right now
(migration to Oracle)and i had a hard tym importing data from excel file to oracle database..i am
using the DTS wizard (Import and export Data in MS SQL Server) to import all the data, i need to
do this over and over again once new data is sent to me(all those are in .xls)..i'm just wondering
if there's a faster way doing all of these..is it possible to code this one, in pl/sql perhaps? so i could
just use Oracle forms.sorry if this sounds awkward, coz i'm really a newbie here.. thnx..