1. If you have a driver for Speed touch 500 download in your PC and enter in its configuration you can IP setting from there.
2. Second enquiry not clear completely but as I understood you want combine more PCs in one link so you can use broadband router (e.g. Speedtouch 510, Speedtouch 580)
For more information visit
http://www.speedtouch.co.uk/faqs.asp...Pos=5.#routers In Router and wired home networking.