Tutorial in abap

hiiiiii all........

i want to practise abap so am searching for some tutorials on reports, smartforms,objects but am not able to find it.

<b>i want some tutorial so that based on that only i hve to write program...wre all tables n desc of what user wants is mention.like how client gives us the tech_specification wre all detail of what he wants is given n based on that we write prg....</b>

one site i know....

http://www.sapbrain.com/PROJECTS/TECHNICAL/ABAP%20Source%20codes/interactive%20reporting%20sample%20code.html

pls suggest me another site if u know or if ur hvng some tech spec pls frwd me....

thanks