I have been to these ruins twice and think they are fantastic! There is an entry charge which is higher for foreigners (10 or 20 $US I think). I got to Copan by bus. Take a bus to La Entrada from San Pedro Sula and then another bus to Santa Rosa de Copan. It is quite a long trip so I recommend staying overnight in Copan.
The petroglyphic staircase in the main plaza of the Copan Ruins. The petroglyphs have yet to be translated and are actually out of order. The roof was put over them to protect them from the weather. This staircase is the main attraction in Copan.
In Copan beware of young children swarming around the entrance to Copan and in the town of Santa Rosa de Copan. These children are capable of ripping off unsuspecting tourists. I bought a few things off them because I wanted them but please don`t be tempted to give them extra cash or to buy something out of pity as they are often `run` by adults who take all the money off them. Give them food perhaps.