Beamer's author is Till Tantau. Beamer's home page on the Web is at:
where you can find several substantive examples plus downloading and installation instructions.
Norm Matloff at UC Davis has produced a very brief introduction to Beamer. This may be useful if you want to get started in a hurry.
Ki-Joo Kim has created two very nice tutorials that demonstrate many advanced features of Beamer. You can find these tutorials, named beamer_guide.pdf and beamer_pstricks.pdf in: