And in continuing with the secretary analogy (ideas are tumbling from my head like rocks 
), the OP could perhaps save additional time and make life easier by dictating his/her responses into a hand-held digital recorder ($29.95 or so @ Wal-Mart) and utilizing the email person’s time to type them up and send them out.
gmail has good spam filtering.
I forward my other email acounts to gmail, where they get (automatically) de-spammed and sorted into folders according to the source. On one account (work) gmail forwards the messages (less the spam it found) back to where it came from. You need to set up the rules to avoid an endless loop…messages containing the string myaccount@gmail.com do not get forwarded to gmail a second time.
Today’s “Kim Komando Tip of the Day” is SpamBayes. But like Kevbo, I think Gmail does an awesome job at filtering spam.