You need a wireless Adsl or router.
Assuming you want it for internet, you will need to set your adsl up with an SSID (Network name)... can be pretty much anything you like eg kiwinest, or dagwood, or crocodile316....anything really. You will need some sort of wep or wpa pass code. I think the 510 will only use a wep key whereas most modern ADSL will want WPa type encryption. Ahh no, I see it will use Wpa-2 that is good.
Then too, connection speed is an issue....As I recall, the 510 is not fast enough for ADSL2
Probably your best thing would be to take the beast down to your local computer shop....not a chain retailer, but a place that does repairs and upgrades. At the very least, ask them for an ADSL that is compatable with the 510.
hope this helps.