Ron, you can also get Macro filters, which screw on to the front of your existing lens.
Here's a link to a shot taken with Hoya Macro filters, they can be purchased as a set or individually. I have a couple somewhere that I used in the days of film, from memory they were quite effective.
If you're curious google for "Hoya Macro filters", or "Hoya Macro filter sets" and find the entry for shopbot to get the best price online.