Can I import my customers into Garmin 265w?

Yes, it is doable. You need to do some file conversions first. You might find things more convenient if you save your excel file as a .dbf file.

Additionally, you need to convert your street addresses into coordinates. This is called geocoding. There is GIS software that can make quick work of this procedure, but it's VERY expensive, and if you're asking this question here, I'm figuring that such a method is out of your reach (both cost-wise and learning curve-wise). Alternatively, there's a long way to do this that won't cost anything but time. You can use Google Earth to punch in an address, and then read out the lat/long coordinates for each address. Create new columns in your tables. One column each for lat and long. Once you run through all these, you can convert the file to a .gpx for transfer into your Garmin GPS with GPS Babel.

Possible easy solution

Not sure if you have a bluetooth phone, but I have a blackberry and I sync addresses from my laptop to blackberry. When I pair my blackberry and Garmin 265wt it automatically pulls up address book from blackberry. Just click phone icon, then phone book and there they are, it also gives me the name and has "2 numbers" next to their name if I have a home and cell number in my phone for them. Then I select their name and which number I want to call. It will also pull up call history from phone. I am a pest tech, so lunch is usually onl the go :) as you probably know. I save the grills on phone and gps from points of interest, so I can call in order between stops. All of guys at work laughed at me at first, but after one of them got hungry between stops while riding with me and we used it, they all do it now. Hope this helps.

Transfering address book

Thanks, for your guidance in using my contact list on my phone to call my customers using Nuvi265W. Do you know how we can use the addresses from my phone to GPS?