The path of the Druid in many ways resembles modern day Wicca. This is because modern Wicca drew a lot from the traditions and legends of Western Europe. Such traditions contain a lot of information from the Celtic peoples, to which the Druids were the priestly class.
The way of the Druid, at its roots is very shamanic. In legend, it was the Druids that the Celts went to for help in healing, for advice in what days were most auspicious for certain workings. They dealt with the spirit world on behalf of the common man. They were the keepers of wisdom; part of the duties of the Druid historically was to memorize the heritage of the people. Since the Celts did not believe in setting things down to writing, this was very important.
Today, Druids work tirelessly to recover the forgotten secrets of the Celts. They work to heal the damage humanity has done to the earth. The majority of today's Druids believe firmly in the Celtic philosophy that honour is very important, and setting a good example is the best way to bring about change in the world.
Druids celebrate the four cross quarter festivals (those days which are halfway between equinox and solstice) and most also celebrate the solstices, equinoxes, and esbats. Druid magick utilizes the natural energies of nature.
Druidry is misunderstood by many today, thanks mainly in part to the Romans during their campaign to subjugate the Celts. Caesar, who cannot necessarily be trusted to be an unbiased writer, unfortunately hands much of the surviving information on the original Druids down to us. Then, later, Druidry survived mainly as a "Men's Club". Taking on the aspect of a kind of Masonic lodge, it became a secret society for upper-class men. Due to the Men's club formation, many people today believe that only men can be Druids, even though Celtic mythology is full of the mention of Druidesses.
Eventually though, there was a break away from the Men's club organization. The Druid order known as the O.B.O.D (Order of Bards, Ovates and Druids) broke away, wishing to shed the strict secrecy of the Masonic structure, and try to rediscover the original philosophy of Druidry. Now, Druid order abound, with as many varying "traditions" within the path as there are within Wicca. The OBOD, the ADF, and many other orders are out there, and a simple websearch will result in many options for Internet based courses, some free, some for a modest fee.
There are three aspects to Druidry in just about every order you will come across. The Druid, the Ovate (Seer), and the Bard. Traditionally, the Druid was kind of a jack-of-all-trades a person whom studied all the arts involved, and did not specialize. Seers were those whom specialized in divination and augury. The Bards were the storytellers, the recorders of history and the makers of teaching songs.
Traditionally, the course of study to become a Druid took 10 years to complete. A good portion of this involved the memorizing of histories, stories, heredity, and the laws. The Druids wisdom was put before anything else. In fact there were legends of Druids being able to stand between to armies on the brink of battle and prevent them from doing battle.
If you would choose to walk the Druids path, I would warn you that it is an often hard and long path, not to be taken up casually