In Hinduism we do not call any teacher a Guru. We do not call preachers as Guru. We do not call mendicants and those who perform the rituals as Guru. Guru is supreme God according to the truth revealed by Hinduism thousands of years ago. A Guru is God in all the senses. We believe that God comes in human form as guru to give salvation to his disciples. The definite text on Guru is Guru Geeta, which sings Guru's glory.
Guru is all around the world. He make look confined in a body but that is only the way he communicates himself. Otherwise he creates the world within himself and destroys it. He gives the results to all of us according to our karma. He shows us the path by which we attain our Godhood. According to Hinduism, every soul is God and by removing the outer layers of ignorance Guru reveals to us our true form.
Guru is all-powerful. Guru creates, sustains and destroys. If one maintains a good life then after certain births one gets a Guru. Not everybody can reach a Guru. I have tried to persuade few people to go to Guru but somehow they never went. I asked this question to my Gurudeva and he told me that not everyone is destined for that
Guru term is used very loosely in the western society and true seekers get confused because of this. My advice to anyone who is looking for a Guru is to pray to God. God will surely one day make that person meet his/her Guru and that day their salvation will begin.
Most of all you will find that those who are true Gurus avoid mentioning this whereas those who are ordinary beings call them selves as Gurus. It is very difficult to explain about what happens after you meet a guru. The changes will tell you that something totally different is happening to you. You will then understand the glory of Guru.