Do you
just want coordinates, or do you want graphical maps with coordinates? If it is the first, then I believe there are publicly available databases, or even purchaseable data snapshots that you can get. Maybe from the USGS, or even the US Post Office.
The two remote services I have worked with are
and
Each one just provides a simple HTTP GET/POST services, which provides maps to the browser, with a fairly simple list of parameters. This made my job harder, since I had to do a log of logic on the PHP side, assembling arrays of values into strings to post to the remote server.
Maptech apparently also sells a few other interesting things, such as a standalone dedicated mapping server (
I have never worked with this, but it looks interesting. MapsOnUs has a fairly limited service, but at least they are cheap. All the others wanted at least 2-3 times as much per year to rent the service.
Really, there are a lot of different services out there that can do what you want, and I'm sure that for the right price, there are some that are configured as a full web servics, with XML/SOAP methods, etc... to make it far easier to connect to a remote API. It just comes down to defining exactly what you want to do, and then examining a lot of choices, to see what they can offer. Most of these systems allow you to do a "test drive" for free, or even use a limited part of the API in production for free.
Beyond that, there is no software I know of that is specifically set up to integrate the two, although I have done some work in that area with PHP. It really is not that complicated if you just want to send address requests to a mapping server and get the coordinates back. -------------------------------------------
"Now, this might cause some discomfort..."
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