It’s worth noting that the reason we flew instead of travelling by train
to Gotland was the absolute impossibility of transporting the bikes by
train or bus across Sweden and on to the ferry to Gotland. Not all Swedish
trains carry bikes, and the carrier service which could have transported
the bikes for us does not visit Oscarshamn, the ferry port for Gotland.
On the other hand, there were many bicycles for hire in Visby, some of
them with little waggons attached, of which we saw many on the roads. If
you can dispense with your own bike, that is certainly a solution to the
transport problem.
Another thing to note is that if you travel during the holiday season
in July and August, it’s probably a good idea to book in advance. Much
accomodation can be found on the Internet, but there’s no central tourist
organization which carries all available accomodation, but rather competing
agencies, some private, some official which each have their own address
list.