An excellent "beginners guide", although you can't beat experiential practice, for core shamanic process. The global similarities between differing cultural practices have been laid bare by Harner et al. and form the basis of this "new" shamanism.

If you are unable to find a teacher to teach you, then this is THE best way to explore the processes of journeying and seeing. It would be sensible, however, to tread carefully and follow to the letter what Harner writes. There is good reason why he is considered an authority, and his advice is to be respected.