Nope. Would like to know too...

The nuvi 200 does not have mp3 as a option but you can get it to use wave files for voice alerts.You will need to download a few things.
1.Make sure you have the latest version of poiloader 2.5.2 go to Garmin site if needed to download http://www8.garmin.com/products/poiloader/
2.You will need to download sox-win 14.1.0 Release Candidate.Download at http://sourceforge.net/project/showfiles.php?group_id=10706 .Unzip the file and place it in your Garmin folder at the same location as poi loader.Go to my computer,click local disc c,click on Garmin folder and you will see poiloader file.This is the location for the unzipped sox file to be placed.
3.You will need a program to convert mp3 files to wave.Wave file will need to be downloaded as PCM 44.100kHz 16 Bit, Mono. A lot of people use Audacity.You can download at http://audacity.sourceforge.net/
4.Now find or make a mp3 file.Convert in accordance with line 3 and add to one of your files.

Example.
>My Pois=Main Folder
>>Food=Subfolder
>>>Cracker Barrel.csv
>>>Cracker Barrel.bmp
>>>Cracker Barrel.wav

5.Run PoiLoader to download file to Gps and use manual mode and select alert distance.

I use this site for your step 3 (ie Costco ahead) http://www.research.att.com/~ttsweb/tts/demo.php

I see on the FAQ it saves as a wave file.This would come in handy taking out the extra step of converting.Some users even with the mp3 units have been using the wave files because of skipping problems with the mp3 format.Not sure of all the models that have the problem but this could come in handy.

hi ive mp3 in my gps but still i cnat hear sound from wave file .can anyone tell me how save wave file as mp3 files

You can search the web for convert wave to mp3.I found this one.You can click on the free version. http://www.nch.com.au/switch/switchsetup.exe

Here are some pre-recorded mp3 sounds. http://www.gpspassion.com/forumsen/topic.asp?TOPIC_ID=106141

Hi,

Again, as mentionned before, you could use "Audacity" audio programm to open your MP3 file and convert them in WAV file, or vice versa....
Very easy process

Just last week I converted all of my personnals audio alerts from MP3 to WAV because of some problems when I listen to MP3 songs from my SD Card but once loaded in my Garmin660 as WAV I just could'nt hear them (the alerts) anymore.

I switched them back to MP3 but still stock with my problem !!!

Any clues anyone ???

When you tried the wave files did you steps 1 and 2 on my above post.I seen other posts with mp3's skipping when using the alerts.Some have had good results using the wave files.What model Garmin do you have?