You can get bullet connectors at any NAPA, Pep Boys, Wal-Mart, etc. You will also need a crimping tool.
They don't have to be soldered. Be sure to get the correct size connectors...blue should work, but you may have to fold the thin gauge wire over a couple of times. You'll also need a connector for the ground wire. I use the kind that have a loop and ground it to the frame.