Yes, Google Sites is not a troop-specific service. It provides generic tools which I have found very useful for other nonprofits.
Sites does not provide any sort of mailing list service, which is definitely a limitation. One way to make announcements work would be to create a Google Group and link it to the website, which I think provides a notification option.
Google Apps for Business is also free for nonprofits and provides a lot more services including mailing lists. However I have found it to be too complex for smaller orgs.
The Docs spreadsheet is flaky if your internet ser