WordNet (r) 3.0 (2006):

hook up
    v 1: connect or link; "hook up the houses to the gas supply
         line"; "Hook up the components of the new sound system"

Moby Thesaurus II by Grady Ward, 1.0:

93 Moby Thesaurus words for "hook up":
   act in concert, act together, affiliate, ally, amalgamate,
   associate, band, band together, be in cahoots, be in league,
   bridle, bunch, bunch up, cabal, cement a union, centralize, club,
   club together, coact, coalesce, collaborate, collude, combine,
   come together, concert, concord, concur, confederate, consociate,
   consolidate, conspire, cooperate, couple, do business with,
   federalize, federate, fetter, fuse, gang, gang up,
   get heads together, get together, go in partners,
   go in partnership, go partners, halter, hang together, harmonize,
   harness, hitch up, hold together, hook up with, join, join forces,
   join fortunes with, join in, join together, join up with,
   join with, keep together, league, league together,
   make common cause, marry, merge, organize, pair, pair off, partner,
   play ball, pull together, put heads together, reciprocate, saddle,
   stand together, stand up with, team up, team up with, team with,
   tether, throw in together, throw in with, tie in, tie in with,
   tie up, tie up with, unionize, unite, unite efforts, unite with,
   wed, work together, yoke