You are basically after a manual here.. These are not simple quick answer questions.
Regarding selecting raw stock for bonsai, I wrote a little guideline how I think one should go about selecting:
www.growingbonsai.net/growing-bonsai-you...ry-stock-for-bonsai/
Wat type of tree is good for beginners.. Depends on where you live. In the tropics a larch would be no good. And in norway a ficus is not ideal.
In general juniper, maples, larch, ligustrum, elms are good species that take a lot of abuse if growin in their natural climatic regions.
From seed to a decent small bonsai is a 15-20 year process most of the time (Although I have made mame sized bonsai in 4 years from berry seedlings). If you o the seed route, ALSO buy some plants. Growing from seed is mainly that. Growing. (Some background info:
www.growingbonsai.net/growing/propagation/)