There really isn't all that much to it. We take daily refuge in the triple-gem (Buddha, Dharma and Sangha), obey the 5 precepts and do our best to follow the Noble Eight-Fold Path.
Many roads lead to the path, but basically there are only two: reason and practice.
Not sure, but why would you want to? Why Budda. There is a loving Heavenly Father, His Son Jesus Christ who is the Savior of the World and the Holy Ghost is the Comforter that teaches all truth. Budda teaches good, but God's first commandment says to not worship any other God but Him. I highly advise not to worship someone other than God Himself.
Visit a temple in your area and speak to one of the monks. S/he will most likely ask you to attend services and learn the teachings before. They do not, generally, have a "baptism" so it wouldn't be as significant as becoming a Christian or Jew. In a sense, I have known many Christian's to attend Buddhist services. There is actually a nun that frequents the temple here in my city. She is not there to warn people away, she actually answers questions to Christian's who are curious.
If you agree with Buddhist teachings, as the appeal to your judgment and reason, you are a Buddhist.
After that it is a matter of self-respect, that you would want to learn more and benefit from what others have discovered. I recommend reading up on the 8 Fold Path. I'm fond of the lessons of Right-Speech, as this discipline is most beneficial.
Meditation practice is one of the greatest gifts of the tradition. I recommend Zazen, but there are many forms. The temples are very open and welcoming places. Check them out and see what they are up to. Finding a teacher is invaluable, so see if you click with anyone.
You should endeavor to learn more about Buddhism and to practice the Buddha's teachings. After you have seen for yourself the truth of them through thorough investigation, you should then think about committing yourself to the practice of Buddhism. Other religions are happy to make a convert of anyone - even young children or the old and incapacitated! Buddhism isn't like that. We want you to think about your decision, be informed, and develop your faith based on your own experience. Every time you learn something, test it out in your own life. Does it lead to good results or bad results? Do good people act like this? If you find it leads to good results, if you find it's the practice of virtuous people, only then should you take the teachings to heart.
In brief, to become a Buddhist, you take the Three Refuges and the Five Precepts.
The Five Precepts are:
1. Panatipata Brahmani SikhismAdamadiyami
I undertake the precept to refrain from destroying living creatures.
2. Adinnadana veramani sikkhapadam samadiyami
I undertake the precept to refrain from taking that which is not given.
3. Kamesu micchacara veramani sikkhapadam samadiyami
I undertake the precept to refrain from sexual misconduct.
4. Musavada veramani sikkhapadam samadiyami
I undertake the precept to refrain from incorrect speech.
5. Suramerayamajja pamadatthana veramani sikkhapadam samadiyami
I undertake the precept to refrain from intoxicating drinks and drugs which lead to carelessness.
'Going for Refuge' means that you accept the Buddha, his Teachings, and the Buddhist Community.
Buddham saranam gacchami (I go to the Buddha for refuge.)
Dhammam saranam gacchami (I go to the Dhamma for refuge.)
Sangham saranam gacchami (I go to the Sangha for refuge.)
If you wish to find your closest Buddhist organisation
http://www.buddhanet.info/wbd/
(Buddhanet's World Buddhist Directory)
If you wish to discuss Buddhism online:
http://www.dhammawheel.com
(Dhammawheel Buddhist Discussion Forum: Theravada)
or
http://www.dharmawheel.net
(Dharmahwheel Buddhist Discussion Forum: Mahayana and Vajrayana)
If you would like to have free books mailed to you or access ebooks online:
Buddhist E-Library: http://www.buddhistelibrary.org
Forest Dhamma Books: http://www.forestdhammabooks.com
Buddha Educational Foundation: http://budaedu.org/en
Buddhist Publication Society: http://www.bps.lk