Suggest you try Compuserve. Not free but cheap and world-wide. Keep away from Compuserve 2000 or whatever it was called. Go for the original now at Ver 4.
Installing software is obviously a problem if you do not have Admin status, but you don't need the softare at all. Just the contract and the dial-up privileges. I've used it in hotels and on my mobile (that's slow, of course). There are Points of Presence telephone numbers for all the US States and other countries published on the Web.