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you can always use graphic converter...

http://www.lemkesoft.de/en/index.htm

i believe it's $30.. not a bad deal and opens darn near anything, i use it for mass thumbnailing of images for my website

also if you plan to do a lot of editing of photos.. maybe photoshop elements? i've got it on my list of apps to get but at the moment can't justify the $50 for the academic version right now.. too many bills too little money 😛 so i know what you're saying...
 
Assuming you have a relatively recent machine;

If you have a pro machine (PowerBook, PowerMac) you will have GraphicConverter which can add text to pictures.

If you have a consumer machine (iMac, iBook, Mac Mini) you should have a copy of AppleWorks which can also add text to pictures.
 
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