You can create your very own custom locations & custom marker icons using My Map on Google maps.
When you are logged into your Google Maps account. In the My Map section Create new Map.
There will be 3 buttons at the top of the page.
Select Icon (Move Icon)
Insert placemark (Default Icon)
To Add a new custom Icon.
Select the Middle button to Insert Placemark (Default Icon).
Select the map to place the Icon (and edit information in the popup dialog box).
Click the Default Icon (Top Right) > Add an Icon .
You can only add a previously uploaded Images/Icons from a specific URL.
The image will automaticallly resize to max 67x67 pixels - for higher quality, it is best practice to adjust size of the image in advance of uploading.
Google Maps Default Icons >>
To Insert the Google Map with the custom icon (image) on to a Google Sites page:
Click 'link' (top right) > 'Customize and preview embedded map' > Copy the HTML Source Code and paste into the 'HTML' in Google Sites.