This is in Haiti, so address do absolutely no good.
I want to be able to highlight data points by characteristic. For example, I want to be able to highlight all clients for a given credit agent so that I can see exactly what their territory is.
Getting them into KML is no problem, I just have no clue how to analyze them in a GIS program. When I put them in, they're just static dots.
If you don't already have coordinate information and addressing is of no use then how did you locate your clients in GE?
If you are getting your dots into a GIS but are unable to do any analysis with them it's likely that you have brought in point locations only and no other attached attributes to analyze on. It's actually a pretty minor task to add attribute info but the specifics vary by software. What GIS exactly are you using? Whatever the software, you should be able to create a table with all of the desired information and simply join this to your existing plotted points. From there making simple selection by attribute info is fairly straightforward.
I've piloted it by taking some sample points using GPS. We're thinking about purchasing a few hundred Garmin units and measuring all of the meeting locations and many of the client locations.
GRASS would be ideal because it is free, but honestly I'm completely lost when I load up the software. Where is the map? I wish it was a little more plug and play, but in any case I really need help getting started. I'm fine with my Excel file full of coordinates and I have all of the attribute data available to add, but when I convert the points to KML and load them up in a demo version of ARCGIS, I just get these data points and I really don't understand how to manipulate them. I try to click on them, but they're none clickable... really just don't know how to use the software I guess but I have no time to learn everything, I just want to know how to do these specific tasks.
1) if your going to use ArGIS (or any GIS really, free or not) you should look into at least some some basic instruction. Take an online class or have someone tutor you in person on the software you will be using if possible. There is very little plug and play in the GIS world right now.
2) I still don't understand the requirement to purchase GPS units, let alone hundreds of them. How many clients do you have? Could you use a couple of units and plot them one at a time over a certain period of time? I still think you could get away with manually digitizing in the locations. It doesn't sound like you need detailed sub meter accuracy, just good general locations to plot territories. Keep in mind that most smart phones have the ability to log locations now so many of your clients may already have the ability to record and send you their locations with no need for new hardware.
3) if you have the funds to buy hundreds of GPS units, I'd look at moving that from the GPS hardware into software instead. If you want ease of use, well... none of it is very easy to use to a novice but the free / open source stuff can require more technical know how and has less structured support overall.