Sudoku Players' Forum (clone)

Ok, its not a question that everyone can help with but i was just wondering: I know there is only one possible answer for each puzzle but is there always a way to know exactly what number goes in which block, or is there some guessing/trial-and-error necessary.
Sorry if that sounds stupid, but im kinda new at SuDoKu, and im starting to get addicted, but hey, its better than drugs.

Each puzzle by pappocom (and others) has the property that it can be solved with logic alone, for techniques on how to do this check out the links below.

http://www.angusj.com/sudoku/hints.php or
http://www.simes.clara.co.uk/programs/sudokutechniques.htm

If you ever get stuck on a really hard puzzle, then post your puzzle here and someone from the forum will gladly help out.

thank you