On Google Earth is there a way I can save my placemarks so that I can access them from different computers?
Yes.
At the left side of the GE screen should be an area called the Sidebar (if it’s not showing, you can make it appear by clicking View at upper left, then checking Sidebar). This includes a section called Places.
Places offers a tree-style view of map features. One folder displayed there is My Places; another is Temporary Places. You can cut & paste items between these folders, and even (via right click) add your own.
To save a folder, highlight it, right click, and choose “Save place as” - this gives a standard file-save dialog. There are two choices for file format: KML and KMZ (the default); the second is basically a compressed version of the first. You might find KML more interesting, as this is an XML file and thus easily editable - though you need to know what you’re doing if you wish to change it in a way that GE can make sense of.
That sounds like what I’m already doing to create placemarks. How do I make them accessible from elsewhere? I can’t find any wsy go create a user name or anything.
It’s as simple as making the KML file available where needed.
Are you looking to send it to some small number of people? E-mail it. Otherwise, make it accessible on a web page.
Another thing you can do, is store the KML file in Google Docs and make it public. Google Docs will give you the resulting URL. From any computer, point to that URL, and all the places will be imported into GE on that computer.
This tool does something similar. it takes a spreadsheet and creates a KML file from it and publishes it in Google Earth. You’d be doing the same thing, but bypassing the spreadsheet –> KML step.
If you don’t have to do it with Google Earth, you can set markers and make custom maps with Google Maps. You can then access it online from any computer and send the link to that particular map to other people. It’s been a long time since I’ve used it, but I assume you need a google account. From there, it’s as simple as opening Maps and clicking on “My Maps”.