808state, the group that named itself after the venerable machine.
Harmony Central, the biggest web site for musicians.
808Bassheadz, a producers duo from The Netherlands (lot of 808 in their productions).
808tales.com, site about the announced 808 documentary.
TR-808 MIDI kit, simple to install MIDI kit.
DrumLinks.com, URL says it all.
808 Mods, very detailed 808 Modification page.
808 Mods part 2, 808 Modification page part 2.
the-Music-house.com, repairs vintage instruments.
Sonicstate.com, the well-known Sonic state for all your studio needs.
VintageSynth, a site about? Yes, vintage synths.
Hyperreal.org, very complete TR-808 page.
808 Auctions, look for auctions of 808 products at Ebay.com.
Spazzoid.com, for Spazzoid Entertainment.
Sequencer.de/roland/ for another nice website about the Roland TR drummachines.